Il numero romano MMCDXX nel sistema decimale vale: 2420.
MMCDXX in latino si scrive duo milia quadringenti viginti,
mentre in italiano duemilaquattrocentoventi.
MMCDI, MMCDII, MMCDIII, MMCDIV, MMCDV, MMCDVI, MMCDVII, MMCDVIII, MMCDIX, MMCDX, MMCDXI, MMCDXII, MMCDXIII, MMCDXIV, MMCDXV, MMCDXVI, MMCDXVII, MMCDXVIII, MMCDXIX, MMCDXXI, MMCDXXII, MMCDXXIII, MMCDXXIV, MMCDXXV, MMCDXXVI, MMCDXXVII, MMCDXXVIII, MMCDXXIX, MMCDXXX, MMCDXXXI, MMCDXXXII, MMCDXXXIII, MMCDXXXIV, MMCDXXXV, MMCDXXXVI, MMCDXXXVII, MMCDXXXVIII, MMCDXXXIX