Il numero romano MCCLXVI nel sistema decimale vale: 1266.
MCCLXVI in latino si scrive mille ducenti sexaginta sex,
mentre in italiano milleduecentosessantasei.
MCCXLVII, MCCXLVIII, MCCXLIX, MCCL, MCCLI, MCCLII, MCCLIII, MCCLIV, MCCLV, MCCLVI, MCCLVII, MCCLVIII, MCCLIX, MCCLX, MCCLXI, MCCLXII, MCCLXIII, MCCLXIV, MCCLXV, MCCLXVII, MCCLXVIII, MCCLXIX, MCCLXX, MCCLXXI, MCCLXXII, MCCLXXIII, MCCLXXIV, MCCLXXV, MCCLXXVI, MCCLXXVII, MCCLXXVIII, MCCLXXIX, MCCLXXX, MCCLXXXI, MCCLXXXII, MCCLXXXIII, MCCLXXXIV, MCCLXXXV