Il numero romano MMMCDLXXX nel sistema decimale vale: 3480.
MMMCDLXXX in latino si scrive tria milia quadringenti octoginta,
mentre in italiano tremilaquattrocentottanta.
MMMCDLXI, MMMCDLXII, MMMCDLXIII, MMMCDLXIV, MMMCDLXV, MMMCDLXVI, MMMCDLXVII, MMMCDLXVIII, MMMCDLXIX, MMMCDLXX, MMMCDLXXI, MMMCDLXXII, MMMCDLXXIII, MMMCDLXXIV, MMMCDLXXV, MMMCDLXXVI, MMMCDLXXVII, MMMCDLXXVIII, MMMCDLXXIX, MMMCDLXXXI, MMMCDLXXXII, MMMCDLXXXIII, MMMCDLXXXIV, MMMCDLXXXV, MMMCDLXXXVI, MMMCDLXXXVII, MMMCDLXXXVIII, MMMCDLXXXIX, MMMCDXC, MMMCDXCI, MMMCDXCII, MMMCDXCIII, MMMCDXCIV, MMMCDXCV, MMMCDXCVI, MMMCDXCVII, MMMCDXCVIII, MMMCDXCIX