Il numero romano MMMDCLXI nel sistema decimale vale: 3661.
MMMDCLXI in latino si scrive tria milia sescenti sexaginta unus,
mentre in italiano tremilaseicentosessantuno.
MMMDCXLII, MMMDCXLIII, MMMDCXLIV, MMMDCXLV, MMMDCXLVI, MMMDCXLVII, MMMDCXLVIII, MMMDCXLIX, MMMDCL, MMMDCLI, MMMDCLII, MMMDCLIII, MMMDCLIV, MMMDCLV, MMMDCLVI, MMMDCLVII, MMMDCLVIII, MMMDCLIX, MMMDCLX, MMMDCLXII, MMMDCLXIII, MMMDCLXIV, MMMDCLXV, MMMDCLXVI, MMMDCLXVII, MMMDCLXVIII, MMMDCLXIX, MMMDCLXX, MMMDCLXXI, MMMDCLXXII, MMMDCLXXIII, MMMDCLXXIV, MMMDCLXXV, MMMDCLXXVI, MMMDCLXXVII, MMMDCLXXVIII, MMMDCLXXIX, MMMDCLXXX