Il numero romano MMDLXI nel sistema decimale vale: 2561.
MMDLXI in latino si scrive duo milia quingenti sexaginta unus,
mentre in italiano duemilacinquecentosessantuno.
MMDXLII, MMDXLIII, MMDXLIV, MMDXLV, MMDXLVI, MMDXLVII, MMDXLVIII, MMDXLIX, MMDL, MMDLI, MMDLII, MMDLIII, MMDLIV, MMDLV, MMDLVI, MMDLVII, MMDLVIII, MMDLIX, MMDLX, MMDLXII, MMDLXIII, MMDLXIV, MMDLXV, MMDLXVI, MMDLXVII, MMDLXVIII, MMDLXIX, MMDLXX, MMDLXXI, MMDLXXII, MMDLXXIII, MMDLXXIV, MMDLXXV, MMDLXXVI, MMDLXXVII, MMDLXXVIII, MMDLXXIX, MMDLXXX