Il numero romano MDCXXIII nel sistema decimale vale: 1623.
MDCXXIII in latino si scrive mille sescenti viginti tres,
mentre in italiano milleseicentoventitré.
MDCIV, MDCV, MDCVI, MDCVII, MDCVIII, MDCIX, MDCX, MDCXI, MDCXII, MDCXIII, MDCXIV, MDCXV, MDCXVI, MDCXVII, MDCXVIII, MDCXIX, MDCXX, MDCXXI, MDCXXII, MDCXXIV, MDCXXV, MDCXXVI, MDCXXVII, MDCXXVIII, MDCXXIX, MDCXXX, MDCXXXI, MDCXXXII, MDCXXXIII, MDCXXXIV, MDCXXXV, MDCXXXVI, MDCXXXVII, MDCXXXVIII, MDCXXXIX, MDCXL, MDCXLI, MDCXLII