18

A neo-nazi code and dog whistle. 1 and 8 refer to the 1st and 8th letters "A+H" of the alphabet, forming an acronym for "Adolf Hitler".

"What's your instagram username?"

"JonAdams18. 18, because I was born on the 18th of July 1996."

"You should be careful with that 18 right there, people might get the impression that you could be a neonazi."