Il numero romano MMMCMLXXI nel sistema decimale vale: 3971.
MMMCMLXXI in latino si scrive tria milia nongenti septuaginta unus,
mentre in italiano tremilanovecentosettantuno.
MMMCMLII, MMMCMLIII, MMMCMLIV, MMMCMLV, MMMCMLVI, MMMCMLVII, MMMCMLVIII, MMMCMLIX, MMMCMLX, MMMCMLXI, MMMCMLXII, MMMCMLXIII, MMMCMLXIV, MMMCMLXV, MMMCMLXVI, MMMCMLXVII, MMMCMLXVIII, MMMCMLXIX, MMMCMLXX, MMMCMLXXII, MMMCMLXXIII, MMMCMLXXIV, MMMCMLXXV, MMMCMLXXVI, MMMCMLXXVII, MMMCMLXXVIII, MMMCMLXXIX, MMMCMLXXX, MMMCMLXXXI, MMMCMLXXXII, MMMCMLXXXIII, MMMCMLXXXIV, MMMCMLXXXV, MMMCMLXXXVI, MMMCMLXXXVII, MMMCMLXXXVIII, MMMCMLXXXIX, MMMCMXC