990 in Roman Numerals
990
C (subtracted)MX (subtracted)C
nine hundred ninety
How CMXC is formed
| Place | Value | Symbols |
|---|---|---|
| Hundreds | 900 | C (subtracted)M |
| Tens | 90 | X (subtracted)C |
| Total | 990 | CMXC |
CMXC is written one place at a time, from the largest to the smallest: CM (900) + XC (90) = 990.
CM and XC are subtractive pairs: in each one the smaller symbol comes first and is taken away.
Common mistakes
Wrong: XM
Why isn't 990 written as XM?
X can only be subtracted from L and C, so XM (1000 − 10) is not a valid pair. Write each place separately: CM (900) + XC (90) = CMXC.
Wrong: DCCCCXC
Why isn't 990 written as DCCCCXC?
A symbol can't be repeated four times in a row. 900 is CM (1000 − 100), not DCCCC, so 990 is CMXC.
Wrong: CMLXXXX
Why isn't 990 written as CMLXXXX?
A symbol can't be repeated four times in a row. 90 is XC (100 − 10), not LXXXX, so 990 is CMXC.
Numbers near 990
Properties of 990
- Prime factors
- 2 × 3² × 5 × 11
- Divisors
- 24 divisors1, 2, 3, 5 … 990
- Even or odd
- Even
- Prime number
- No
- Letters in CMXC
- 4
990,000 in Roman numerals
With a bar over it (vinculum), C̅M̅X̅C̅ means 990 × 1,000 = 990,000. How Roman numerals work