Il numero romano MMMCDXXXI nel sistema decimale vale: 3431.
MMMCDXXXI in latino si scrive tria milia quadringenti triginta unus,
mentre in italiano tremilaquattrocentotrentuno.
MMMCDXII, MMMCDXIII, MMMCDXIV, MMMCDXV, MMMCDXVI, MMMCDXVII, MMMCDXVIII, MMMCDXIX, MMMCDXX, MMMCDXXI, MMMCDXXII, MMMCDXXIII, MMMCDXXIV, MMMCDXXV, MMMCDXXVI, MMMCDXXVII, MMMCDXXVIII, MMMCDXXIX, MMMCDXXX, MMMCDXXXII, MMMCDXXXIII, MMMCDXXXIV, MMMCDXXXV, MMMCDXXXVI, MMMCDXXXVII, MMMCDXXXVIII, MMMCDXXXIX, MMMCDXL, MMMCDXLI, MMMCDXLII, MMMCDXLIII, MMMCDXLIV, MMMCDXLV, MMMCDXLVI, MMMCDXLVII, MMMCDXLVIII, MMMCDXLIX, MMMCDL