Il numero romano MMCLXXXI nel sistema decimale vale: 2181.
MMCLXXXI in latino si scrive duo milia centum octoginta unus,
mentre in italiano duemilacentottantuno.
MMCLXII, MMCLXIII, MMCLXIV, MMCLXV, MMCLXVI, MMCLXVII, MMCLXVIII, MMCLXIX, MMCLXX, MMCLXXI, MMCLXXII, MMCLXXIII, MMCLXXIV, MMCLXXV, MMCLXXVI, MMCLXXVII, MMCLXXVIII, MMCLXXIX, MMCLXXX, MMCLXXXII, MMCLXXXIII, MMCLXXXIV, MMCLXXXV, MMCLXXXVI, MMCLXXXVII, MMCLXXXVIII, MMCLXXXIX, MMCXC, MMCXCI, MMCXCII, MMCXCIII, MMCXCIV, MMCXCV, MMCXCVI, MMCXCVII, MMCXCVIII, MMCXCIX, MMCC