What is the base number of roman numerals?

Answer 1

The system is essentially base 10, since a numeral can always be

broken into parts for each power of ten:

M CM LX VII

1 9 6 7

It's base is: 10

because it represents the state of an abacus (which has ones and fives for each base ten digit),

and agrees with their base ten names for numbers (using hundreds,

thousands, and so on). It is not a _positional_ system (which accounts

for the lack of a zero) but that does not mean it is not a _base ten_

system. I've somewhere heard it described as a sort of mix of bases

five and ten, but I don't think that's really significant. Essentially

it is base ten, with combinations of symbols used for each digit.

Answer 2

The base number of Roman numerals is 10, represented by the letter "X".