You Are Number Six/Literature

Examples of in  include:


 * Walter R. Brooks (creator of Mister Ed) wrote a series of children's novels about Freddy, a talking pig who's also a private detective, and who lives on a farm where all the animals talk. All of the animals on this farm (including the rats and spiders) have names — often very clever and unusual names — except for the rabbits. There are so many rabbits, they just use numbers instead of names.
 * In the Star Wars Expanded Universe, Clone Troopers were assigned numerical designations like RC-1138. During training, they gave each other nicknames, some of them based on something they did, like Scorch and Climber, from their numbers, like Forr, Sev, Fi, Niner, Fives and A-98 becoming Nate, or from descriptive Mandalorian words like Di'kut and, well, Nate, who changed his name to Jangotat.
 * One book- either Labyrinth of Evil or the novelization of Revenge of the Sith- makes a note that later batches of clones, particularly the special ops ones, have real names. The one that tends to follow Obi-Wan around, for instance, is named Cody.
 * The X Wing Series assigns each pilot a different number; on missions they are expected to stick rigidly to that number, though the narration still uses names when it comes to squadron members. Twice the significance of numbers is brought up - once, a droid is pleased by the nickname "Thirteen" because this implied that it was the thirteenth member of the twelve-pilot squadron; and in a different book a new pilot smiles about being Two, not knowing that that number, and subsequently being number one's wingmate, is reserved for pilots who aren't fully trusted to fly well and act correctly. The number system is justified in the same book series as a way to reduce the amount of information they're giving away over the comm system, dating from the early days of the Alliance when their identities were actually secret; they deliberately use low-quality systems with poor signal quality for the same reason.
 * The Roman version of this gets referenced in Neil Gaiman's Stardust with the seven brothers Primus, Secundus, Tertius, Quartus, Quintus, Sextus, and Septimus. And their sister, Una.
 * In We, people no longer have names; they are not only referred to by number, but even are called "numbers." For example, the main character's number is D-503.
 * In the novel This Perfect Day by Ira Levin, people in a dystopian future are given "namebers", such as Li RM35M4499, the hero, and Anna SG38P2823, his eventual wife.
 * In the Animorphs series all of the Yeerk names and ranks have numbers attached. The lower numbers are the higher ranked, and different tiers have different sets of numbers. A Visser is just below the Council of Thirteen, the most powerful Yeerks. So when Visser 3 literally spills hate from his mind and is the scariest thing this side of the galaxy, the thought of Visser 1 makes you wanna crap your pants.
 * In a literal example, in the Sword of Truth books, there's a witchwoman named "Six," because the number is a bad omen for witches, and her mother knew she would turn out to be bad. One wonders if being named after a bad omen might have had something to do with it.
 * In Logan's Run characters are Name X, e.g. Logan 3 (5 in the movie).
 * In Holes Hector Zeroni is called Zero by everyone, including Pendanski, who calls everyone else by their real names.
 * Pretty sure there's a good reason for that, as Zero doesn't speak to anyone until Stanley shows up and starts treating him like a younger brother...compassion does wonders, and Zero starts talking and, after the important part of the story, reveals to Stanley who he is/why it's important.
 * Watership Down has Fiver. Rabbits can only count to four, so any number over that is "a great many."
 * In The War of the Flowers by Tad Williams.
 * In the original novel version of A Clockwork Orange, Alex's prison name/number is the slightly longer "6655321".
 * People have serial numbers in Nineteen Eighty-Four; Winston's is 6079.
 * In Erich Maria Remarque's novel, Spark of Life (set in a concentration camp), the protagnist is only called 509, his serial number.
 * In The Giver, people have serial numbers besides their names. When children behave badly, their parents sometimes call him on their numbers, suggesting that a bad child is not worthy of a name. This is related is the fact that, in the community, children's ages are used as nouns rather than descriptions; for example, "a Four" or "all the Elevens". They also use the term "Olds" for the elderly.
 * In Artemis Fowl: The Lost Colony, imps are referred to as numbers until they transform into demons. Imp No1, a major character, decides to keep his number, because "It's my name - it's who I am."
 * Perry Rhodan sometimes uses numbers in alien naming schemes, usually to indicate that the species in question is particularly 'rational', fond of order, or of robotic origin. Sometimes names may get conflated with titles, too—for example, the commander of a Maahk vessel or installation is usually a 'Grek-1', but no other name is generally ever given, leaving the reader to speculate just how those address each other at meetings...
 * They probably refer to each other by what they command.
 * In Terry Pratchett's Interesting Times, and other Discworld novels featuring them, men from the Agatean Empire typically have a name consisting of a number, an adjective, and a noun—for example, One Big River or Six Beneficient Winds. Word of God is "I just wanted a coherent way of making up 'foreign' names and I think I pinched the Mayan construction." Common people seem to shorten their names to the number and noun, such as Twoflower and Ninereeds. This isn't considered particularly dehumanizing, but it is seen as important — in one incidental scene we come across one Two Little Wang, who hasn't been terribly happy with his life up to this point and pins it on being given the unlucky number Two--"Little Wang" is by way of being mildly insulting icing on an already unfortunate and doomed cake. At one point, Cohen messes around with the taxing system, and nicknames one of the beneficiaries "One Lucky Peasant."
 * In the backstory to The Lord of the Rings (The War of the Jewels, if you're curious), there are three Elves named Imin, Tata and Enel, or "One", "Two" and "Three", allowing for linguistic drift. Although considering who they are, it's entirely possible the numbers were named after them rather than the other way around.
 * The first book of The Faerie Queene has a more symbolic version of this. The Love Interest is named Una, standing for the one-ness of the true (Protestant) faith; her nemesis, standing for the "two-faced" Roman Catholic church, is named Duessa. The fourth book has three brothers named Priamond, Diamond and Triamond, according to their order of birth.
 * James Bond, 007.
 * The Count of Monte Cristo. While Edmond Dantès is imprisoned in the Château d'If, a new governor is put in charge. He doesn't want to bother learning the names of the prisoners, so he refers to them by the numbers of their cells. As a result, Dantès is known as Number 34.
 * In the Septimus Heap books, several boys in the Youth Army have numbers for names, notably Boy 412 and Boy 409.
 * Les Misérables: Jean Valjean, Prisoner Two Four Six Oh One.
 * And later 9430.
 * The narrator of Tom Paine Maru gives his name as Whitey O'Thraight—or so it seems, until someone grousing about Whitey's regimented lifestyle sarcastically wonders why his people don't simply use numbers. They do. His name is actually YD-038.
 * In Kevin O'Donnell's novel ORA:CLE, personal names are alphanumeric strings encoding personal attributes (including allotted public time and computer-related knowledge [!]); for example, the main character's name is ALL80 AFAHSC NFF6 (Ale Elatey for short).
 * In the Instrumentality series of stories by Cordwainer Smith, people have numbers instead of names, but to make them a little more personal, they call themselves the last digits of their numbers in old Earth languages: Sto Odin ("101" in Russian), Trece ("13" in Spanish), and so on.
 * In Barbara Hambly's Knight of the Demon Queen the protagonist goes through a variety of Hells to get the quest object and is in a dystopia for a week before realising that it is a real human world and not a hell with some humans trapped in it. In this dystopia people have numbers instead of names, i.e. their SSN is their name.
 * Although these are often shortened into nicknames of a sort, with more common names in front. EX: "Corvin 9550" (Corvin Ninety-Five Fifty).
 * Not technically numbers but very much in the spirit of the trope, the Unsullied in A Song of Ice and Fire take a new name out a barrel at the start of each day. Names along the lines of "Grey Worm". After being freed most of them picked new, less degrading names and stuck with them.
 * Perhaps slightly subverted when one decides to keep the name he randomly drew on the day they were freed because he considers it lucky.
 * Happens a few times in the Vorkosigan universe. In Labyrinth, Miles encounters a genetic construct named Nine; in Ethan of Athos, the fugitive they're chasing is named L-X-10-Terran-C (Terrence Cee as a nickname,) who also had a sister/mate named J-X-Ceta-9 (Janine.) Also turned up in Falling Free; as genetically designed mass-produced free-fall dwellers, many of the original quaddies had names that were adaptations of their serial numbers (eg TNY became Tony, CLR became Claire, etc.)
 * Subverted in Isaac Asimov's robot stories. Robots are given serial numbers, but only ignorant civilians actually use the serial numbers as names; roboticists shorten them to human-sounding nicknames.
 * And played straight in the Foundation cycle: in the Mycogen sector of Trantor people have a "cohort" (family) name and a number for first name, like Mycelium 72, Raindrop 43, Raindrop 45, Sunmaster 14, Skystrip 2.
 * Eight the lynx from Felidae On the Road.
 * Gehn, the Big Bad of one Myst novelisation, has a habit of numbering everything he comes to control, mainly including the worlds he "creates" but extending to the people who inhabit said worlds. He doesn't care if they already had a name, and doesn't see why this might be inappropriate.
 * The First Lord and family in Codex Alera follow the Roman example under Real Life.
 * In the Keys to the Kingdom series, every Denizen has a number denoting their name and "ranking" in the House (lower is invariably better). It is common to hear "Give your name and precedence in the House." The number defines the Denizen's position, and conversely, when the position is changed, the number adjusts itself accordingly. Although most characters encountered are at least in the thousands, Arthur is mentioned as having a rank of 6 at the beginning of Sir Thursday (presumably because 1-5 is composed of the remaining Trustees and some final entity).
 * In the Of Man and Manta series by Piers Anthony, agents are super-humans created from normal people who, for whatever reason, are in a vegetative state. The agents have a two-letter designation which indicates which series they are, but are given names to "humanize" them. The names are generated by their series, e.g. a female agent in the TA series becomes "Tammy".
 * Hugo Gernsback, the namesake of the Hugo Award, wrote a story titled "Ralph 124C41+ " about a typical citizen of a future utopia. Although Ralph's surname appears to be a random serial number, it is actually "One to foresee for all".
 * In the Guardians of Ga'Hoole series, St. Aegolius' Academy for Orphaned Owls gives each owl a number until they became high ranked enough to get a name.
 * The titular character of the Montmorency novels was semiconscious and unable to state his name while put on trial for robbery, so was sentenced under his prisoner number. Likewise, the guards and the doctor who treated his injuries never bothered to ask. We are never actually told his previous name, either.
 * One of Ayn Rand's somewhat lesser known books Anthem had a collectivist Dystopia in which everyone had names like Solidarity-0665 or Union-0934.
 * Replica. All the clones are Amy if girl, Andy if boy. So when they are together, the heroine is Seven.
 * A major character in Syrup by Max Barry is literally named "6". Not even "six", but the Arabic numeral "6".
 * Manpower Inc.'s genetic slaves from Honor Harrington books are given alphanumerical designations.
 * In Star Trek Deep Space Nine: A Stitch In Time, the youths training at the Bamarren Institute are not permitted to use their names; instead they are assigned a group and a number. The number (one to ten) signifies their position within the group, with the higher numbers considered superior. Supposedly, they are numbered according to skill level, but politics and birthright play just as large a role. At the end of each three-year course, the numbers switch, and it is here that lower-born youths with talent can achieve a more deserving position. It's a mix of meritocratic principles and social stratification.
 * I Am Number Four.
 * John C. Wright uses this in Chronicles of Chaos, borrowing the Roman style of naming children in the order in which they are born. The children pick names for themselves before the series starts, however, with Primus becoming Victor Invictus Triumph, Secunda becoming Amelia Armstrong Windrose, Tertia becoming Vanity Bonfire Fair, and Quartinus becoming Colin Iblis mac FirBolg, but Quentin doesn't wish to change his name and becomes Quentin Nemo.
 * In the Tamir Triad trilogy by Lynn Flewelling, independent mages are forced to register to the King's personal mages to receive a number they are to wear all time. That's when Iya understands the meaning of the number she had seen in an oracle years before: 222.
 * Humans in The Madness Season have not had real names for centuries, instead given a numerical designation in the language of their Tyr overlords. That includes the main character who had been designated Daetrin Ungashak To-Alym Haal (or just Daetrin to his friends).
 * The Cat in the Hat has his assistants, Thing 1 and Thing 2.
 * The dictator in "Happy Ending" by Fredric Brown and Mack Reynolds calls himself Number One.
 * The dictator in "Happy Ending" by Fredric Brown and Mack Reynolds calls himself Number One.