Il numero romano MMDCXXIII nel sistema decimale vale: 2623.
MMDCXXIII in latino si scrive duo milia sescenti viginti tres,
mentre in italiano duemilaseicentoventitré.
MMDCIV, MMDCV, MMDCVI, MMDCVII, MMDCVIII, MMDCIX, MMDCX, MMDCXI, MMDCXII, MMDCXIII, MMDCXIV, MMDCXV, MMDCXVI, MMDCXVII, MMDCXVIII, MMDCXIX, MMDCXX, MMDCXXI, MMDCXXII, MMDCXXIV, MMDCXXV, MMDCXXVI, MMDCXXVII, MMDCXXVIII, MMDCXXIX, MMDCXXX, MMDCXXXI, MMDCXXXII, MMDCXXXIII, MMDCXXXIV, MMDCXXXV, MMDCXXXVI, MMDCXXXVII, MMDCXXXVIII, MMDCXXXIX, MMDCXL, MMDCXLI, MMDCXLII