It is the equivalent of 313 = CCCXIII
20
1993
That is not a proper Roman Numeral
In roman numrals it means 2011
It is: XVI = 16
It is: DCCXXX = 730
li or LI = 51
In today's notation they represent 390
C represents 100, I is 1 and X is 10. this would be shown as CCCXIII.
D
LV
MCXVII