What is 1000000000000000000000 in roman numerals?

Answer 1

Under the accepted conventions, it is not possible to represent 1,000,000,000,000,000,000,000 in Roman numerals. Convention has it that M may not be repeated more than 3 times in succession (M=1,000), thus MMMCMXCIX (3999) is the largest possible Roman numeral.

Breaking with convention the number would require 1,000,000,000,000,000,000 successive Ms, but this would clearly be unacceptable to us, never mind the Romans.

However, the original symbol for 1,000 wasn't the letter M, it was the symbol CIƆ. This is often credited as the origin of the infinity symbol (∞). Under this system, the notation can be extended such that the value is multiplied by a factor of 10. Thus CCIƆƆ represents 10,000. Extending the notation further, 1,000,000,000,000,000,000,000 could be represented as:

CCCCCCCCCCCCCCCCCCC|ƆƆƆƆƆƆƆƆƆƆƆƆƆƆƆƆƆƆƆ