Il numero romano MDCCLXXXI nel sistema decimale vale: 1781.
MDCCLXXXI in latino si scrive mille septingenti octoginta unus,
mentre in italiano millesettecentottantuno.
MDCCLXII, MDCCLXIII, MDCCLXIV, MDCCLXV, MDCCLXVI, MDCCLXVII, MDCCLXVIII, MDCCLXIX, MDCCLXX, MDCCLXXI, MDCCLXXII, MDCCLXXIII, MDCCLXXIV, MDCCLXXV, MDCCLXXVI, MDCCLXXVII, MDCCLXXVIII, MDCCLXXIX, MDCCLXXX, MDCCLXXXII, MDCCLXXXIII, MDCCLXXXIV, MDCCLXXXV, MDCCLXXXVI, MDCCLXXXVII, MDCCLXXXVIII, MDCCLXXXIX, MDCCXC, MDCCXCI, MDCCXCII, MDCCXCIII, MDCCXCIV, MDCCXCV, MDCCXCVI, MDCCXCVII, MDCCXCVIII, MDCCXCIX, MDCCC