You Are Number Six/Comic Books


 * The Beagle Boys in Disney comics are all identical and distinguished only by their prison numbers. In one Don Rosa story they discuss the fact that none of them can even remember their real names, and another time Rosa has one of them reminisce how his mother expected to get a bribe to reveal his name to him, as a child.
 * BI66ER from the comic stories of The Matrix.
 * In Marvel Comics, X-51 is the robotic Machine Man Aaron Stack's original name, but he hates being called that.
 * Also from Marvel, Shatterstar's alternate name is Gaveedra-Seven.
 * 711, a short-lived Golden Age character who first appeared in Police Comics #1 (the same book in which Plastic Man debuted). He was unjustly imprisoned and "711" was his prisoner number. He tunneled his way out of prison so he could fight crime every night and return to his cell every morning, no one the wiser.
 * V for Vendetta: V's name was derived from being an experiment who was in room five, which has the Roman numeral V. Not that the comic's version considered it a name as such.
 * X23 from X-Men, . Also, Fantomex. His real name is Charlie-Cluster 7, while his official codename is Weapon XIII. Last but not least: Wolverine himself, as he is Weapon X.
 * 355 in Y: The Last Man.
 * PS238 has Julie Finster who gets the name "Eighty Four" from her classmates because she is the 84th metahuman with the F.I.S.S. package (Flight, Invulnerability, Strength, Speed). Since it's more common than the Most Common Superpower in that 'verse, F.I.S.S. tend to get the short end of any available stick and with a few exceptions are dismissed by metahumans with more gimmicky powers as un-cool "grunts". Later on, after chatting with several other FISS metahumans she chose to adopt "84" as her official Superhero Name, and wear the number on her costume.
 * The latter move unexpectedly caused an avalanche, as some other F.I.S.S. followed the example, then started an organization of their own and began to recruit the rest. And named it "Infinite Vanguard". Official Super Teams with commercial side (from contracts to selling action figures of their members) were already common, but the sheer size wasn't, and moved this club into a category of its own. They are the most numerous type.
 * Also from Marvel, Agents Of S.H.I.E.L.D. go by code numbers. Sharon Carter is Agent 13.
 * In the Doctor Who Magazine comic strip, the Thinktwice prison wipes the memories of its inmates, including all the details of their identity. The Doctor finds Corrupt Corporate Executive Majenta Pryce there, where she's known as MP8/1/14/4 or "EmPee".
 * The seven adopted children who form The Umbrella Academy respond to their respective numbers up until they receive real names and proper superhero codes name, respectively. Number Six himself dies very, very early on in the series.
 * The main characters of WE 3. Their real names are Bandit (the dog), Tinker (the cat), and Pirate (the rabbit).
 * Harold Higgins, who was featured in Daredevil Comics, fought crime as the superhero 13.
 * The main characters from Mike Allred's underrated miniseries Red Rocket 7 are all clones of a heroic alien set to return one day. They're all numbered 2-7 and named as such.
 * In Marvel's G.I. Joe series, Crimson Guardsmen of the "Fred" series all took the name Fred followed by a Roman numeral, and had plastic surgery so they all looked alike. As the Freds were all infiltrating corporations and politics, this allowed any Fred to replace another should the need arise.
 * Superboy (Conner Kent) was original designated "S-13", as in being the 13th (and only successful) attempt at cloning Superman.
 * The character from the adventure strip The Q Bikes (and later the Q Karts and parodied as the Q Shoes in Viz) from The Beano had names but the characters were also identified by numbers Q1, Q2, etc. up to Q6.
 * Subverted rather bizarrely in Marvel by Dr. 13: real name, Dr. Terrence Thirteen. His daughter Traci Thirteen is there too.
 * Marvel's Secret Empire is a subversive criminal organization headed by ten people who refer to themselves as Number One through Number Ten, with Number One being the leader. The original Number One was killed in the organization's first appearance, and anyone holding that title never holds it longer than one arc. Some arcs have involved the other nine trying to find a replacement. It's almost become a Running Gag.