Il numero romano CDXXVIII nel sistema decimale vale: 428.
CDXXVIII in latino si scrive quadringenti viginti octo,
mentre in italiano quattrocentoventotto.
CDIX, CDX, CDXI, CDXII, CDXIII, CDXIV, CDXV, CDXVI, CDXVII, CDXVIII, CDXIX, CDXX, CDXXI, CDXXII, CDXXIII, CDXXIV, CDXXV, CDXXVI, CDXXVII, CDXXIX, CDXXX, CDXXXI, CDXXXII, CDXXXIII, CDXXXIV, CDXXXV, CDXXXVI, CDXXXVII, CDXXXVIII, CDXXXIX, CDXL, CDXLI, CDXLII, CDXLIII, CDXLIV, CDXLV, CDXLVI, CDXLVII