Il numero romano MCCLI nel sistema decimale vale: 1251.
MCCLI in latino si scrive mille ducenti quinquaginta unus,
mentre in italiano milleduecentocinquantuno.
MCCXXXII, MCCXXXIII, MCCXXXIV, MCCXXXV, MCCXXXVI, MCCXXXVII, MCCXXXVIII, MCCXXXIX, MCCXL, MCCXLI, MCCXLII, MCCXLIII, MCCXLIV, MCCXLV, MCCXLVI, MCCXLVII, MCCXLVIII, MCCXLIX, MCCL, MCCLII, MCCLIII, MCCLIV, MCCLV, MCCLVI, MCCLVII, MCCLVIII, MCCLIX, MCCLX, MCCLXI, MCCLXII, MCCLXIII, MCCLXIV, MCCLXV, MCCLXVI, MCCLXVII, MCCLXVIII, MCCLXIX, MCCLXX