Il numero romano MDCCXX nel sistema decimale vale: 1720.
MDCCXX in latino si scrive mille septingenti viginti,
mentre in italiano millesettecentoventi.
MDCCI, MDCCII, MDCCIII, MDCCIV, MDCCV, MDCCVI, MDCCVII, MDCCVIII, MDCCIX, MDCCX, MDCCXI, MDCCXII, MDCCXIII, MDCCXIV, MDCCXV, MDCCXVI, MDCCXVII, MDCCXVIII, MDCCXIX, MDCCXXI, MDCCXXII, MDCCXXIII, MDCCXXIV, MDCCXXV, MDCCXXVI, MDCCXXVII, MDCCXXVIII, MDCCXXIX, MDCCXXX, MDCCXXXI, MDCCXXXII, MDCCXXXIII, MDCCXXXIV, MDCCXXXV, MDCCXXXVI, MDCCXXXVII, MDCCXXXVIII, MDCCXXXIX