313
313 is the year the Edict of Milan legalised Christianity in the Roman Empire.
- Odd
- Prime
Where 313 fits
Why 313 is special
It granted toleration to all religions rather than privileging Christianity, which came later. The distinction is routinely collapsed in accounts that treat 313 as the conversion of the empire.
Factors & digit properties
- Divisors (2)
- 1, 313
- Prime factorisation
- 313
- Digit sum
- 7
- Digital root
- 7
Representations
- Decimal
- 313
- Binary
- 100111001
- Octal
- 471
- Hexadecimal
- 139
- Roman numeral
- CCCXIII
- Scientific notation
- 3.130 × 10^2
Other mathematical patterns
- Palindromic number
- Deficient number
- Happy number
- Twin prime
Law & regulation
The Edict of Milan extended legal protection to all cults, Christianity included. Christianity became the state religion in 380, and conflating the two dates misstates what changed in 313.
DocumentedLaw & regulationGeography: Roman EmpirePeriod: 313
Common questions
Is 313 a prime number?
Yes, 313 is prime — it has exactly two positive divisors: 1 and itself.
What are the factors of 313?
The factors of 313 are 1, 313.
What is 313 in Roman numerals?
313 in Roman numerals is CCCXIII.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 3 August 2026