431 in Roman Numerals
431
C (subtracted)DXXXI
four hundred thirty-one
How CDXXXI is formed
| Place | Value | Symbols |
|---|---|---|
| Hundreds | 400 | C (subtracted)D |
| Tens | 30 | XXX |
| Units | 1 | I |
| Total | 431 | CDXXXI |
CDXXXI is written one place at a time, from the largest to the smallest: CD (400) + XXX (30) + I (1) = 431.
CD is the only subtraction: the C before the D takes away 100, so CD = 400.
Common mistakes
Wrong: CCCCXXXI
Why isn't 431 written as CCCCXXXI?
A symbol can't be repeated four times in a row. 400 is CD (500 − 100), not CCCC, so 431 is CDXXXI.
Numbers near 431
Properties of 431
- Prime factors
- 431
- Divisors
- 1, 431
- Even or odd
- Odd
- Prime number
- Yes
- Letters in CDXXXI
- 6
431 is a prime number: it can only be divided by 1 and by itself.
431,000 in Roman numerals
With a bar over it (vinculum), C̅D̅X̅X̅X̅I̅ means 431 × 1,000 = 431,000. How Roman numerals work