Il numero romano MMDCCCLXI nel sistema decimale vale: 2861.
MMDCCCLXI in latino si scrive duo milia octingenti sexaginta unus,
mentre in italiano duemilaottocentosessantuno.
MMDCCCXLII, MMDCCCXLIII, MMDCCCXLIV, MMDCCCXLV, MMDCCCXLVI, MMDCCCXLVII, MMDCCCXLVIII, MMDCCCXLIX, MMDCCCL, MMDCCCLI, MMDCCCLII, MMDCCCLIII, MMDCCCLIV, MMDCCCLV, MMDCCCLVI, MMDCCCLVII, MMDCCCLVIII, MMDCCCLIX, MMDCCCLX, MMDCCCLXII, MMDCCCLXIII, MMDCCCLXIV, MMDCCCLXV, MMDCCCLXVI, MMDCCCLXVII, MMDCCCLXVIII, MMDCCCLXIX, MMDCCCLXX, MMDCCCLXXI, MMDCCCLXXII, MMDCCCLXXIII, MMDCCCLXXIV, MMDCCCLXXV, MMDCCCLXXVI, MMDCCCLXXVII, MMDCCCLXXVIII, MMDCCCLXXIX, MMDCCCLXXX