FromCharacterCode

FromCharacterCode[n] gives a string consisting of the character with integer code n.

FromCharacterCode[{n1, n2, ...}] gives a string consisting of the sequence of characters.

Examples

Single character:

FromCharacterCode[65]
(* "A" *)

String from codes:

FromCharacterCode[{72, 101, 108, 108, 111}]
(* "Hello" *)

Please visit the official Wolfram Language Reference for more details.