400 in Roman Numerals
400
C (subtracted)D
four hundred
How CD is formed
| Place | Value | Symbols |
|---|---|---|
| Hundreds | 400 | C (subtracted)D |
| Total | 400 | CD |
CD is a subtractive pair: C written before D means 500 − 100 = 400.
Common mistakes
Wrong: CCCC
Why isn't 400 written as CCCC?
A symbol can't be repeated four times in a row. 400 is CD (500 − 100), not CCCC.
Numbers near 400
Properties of 400
- Prime factors
- 2⁴ × 5²
- Divisors
- 15 divisors1, 2, 4, 5 … 400
- Even or odd
- Even
- Prime number
- No
- Letters in CD
- 2
400 is a perfect square: 20 × 20.
400,000 in Roman numerals
With a bar over it (vinculum), C̅D̅ means 400 × 1,000 = 400,000. How Roman numerals work