Il numero romano MMDCLXI nel sistema decimale vale: 2661.
MMDCLXI in latino si scrive duo milia sescenti sexaginta unus,
mentre in italiano duemilaseicentosessantuno.
MMDCXLII, MMDCXLIII, MMDCXLIV, MMDCXLV, MMDCXLVI, MMDCXLVII, MMDCXLVIII, MMDCXLIX, MMDCL, MMDCLI, MMDCLII, MMDCLIII, MMDCLIV, MMDCLV, MMDCLVI, MMDCLVII, MMDCLVIII, MMDCLIX, MMDCLX, MMDCLXII, MMDCLXIII, MMDCLXIV, MMDCLXV, MMDCLXVI, MMDCLXVII, MMDCLXVIII, MMDCLXIX, MMDCLXX, MMDCLXXI, MMDCLXXII, MMDCLXXIII, MMDCLXXIV, MMDCLXXV, MMDCLXXVI, MMDCLXXVII, MMDCLXXVIII, MMDCLXXIX, MMDCLXXX