Il numero romano CDXII nel sistema decimale vale: 412.
CDXII in latino si scrive quadringenti duodecim,
mentre in italiano quattrocentododici.
CCCXCIII, CCCXCIV, CCCXCV, CCCXCVI, CCCXCVII, CCCXCVIII, CCCXCIX, CD, CDI, CDII, CDIII, CDIV, CDV, CDVI, CDVII, CDVIII, CDIX, CDX, CDXI, CDXIII, CDXIV, CDXV, CDXVI, CDXVII, CDXVIII, CDXIX, CDXX, CDXXI, CDXXII, CDXXIII, CDXXIV, CDXXV, CDXXVI, CDXXVII, CDXXVIII, CDXXIX, CDXXX, CDXXXI