V in roman numerals is 5, but I don't know if that answers your question because of your syntax.
roman numarals are v,i ,x,c and some other stuff with represent numbers
V is 5. I is 1. VI is 6.
C represents 100 (a Century is 100 years). The L represents 50. The fact that the I (one) comes before the V (5) means you subtract it. So it represents 154.
XII
Your answer is XXI
L
CCCLXII
XII
538
1 = I
DCC
XXXIX