Il numero romano MDCCCLI nel sistema decimale vale: 1851.
MDCCCLI in latino si scrive mille octingenti quinquaginta unus,
mentre in italiano milleottocentocinquantuno.
MDCCCXXXII, MDCCCXXXIII, MDCCCXXXIV, MDCCCXXXV, MDCCCXXXVI, MDCCCXXXVII, MDCCCXXXVIII, MDCCCXXXIX, MDCCCXL, MDCCCXLI, MDCCCXLII, MDCCCXLIII, MDCCCXLIV, MDCCCXLV, MDCCCXLVI, MDCCCXLVII, MDCCCXLVIII, MDCCCXLIX, MDCCCL, MDCCCLII, MDCCCLIII, MDCCCLIV, MDCCCLV, MDCCCLVI, MDCCCLVII, MDCCCLVIII, MDCCCLIX, MDCCCLX, MDCCCLXI, MDCCCLXII, MDCCCLXIII, MDCCCLXIV, MDCCCLXV, MDCCCLXVI, MDCCCLXVII, MDCCCLXVIII, MDCCCLXIX, MDCCCLXX