999 in words
999
nine hundred and ninety-nine
999 is written nine hundred and ninety-nine.
Ways to write it
- As an ordinal
- nine hundred and ninety-ninth
- Roman numeral
- CMXCIX
- Expanded form
- 900 + 90 + 9
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 9 | 900 |
| tens | 9 | 90 |
| ones | 9 | 9 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 9, 27, 37, 111, 333 and 999 (8 factors)
- First 10 multiples
- 999, 1,998, 2,997, 3,996, 4,995, 5,994, 6,993, 7,992, 8,991, 9,990
- Square
- 999 × 999 = 998,001
- Square root
- ≈ 31.61
- Sum of the digits
- 9 + 9 + 9 = 27
- Rounded to the nearest 10
- 1,000
- Rounded to the nearest 100
- 1,000
- Number before
- 998
- Number after
- 1,000
- In binary
1111100111
Quick check
What number comes just after 999?
Show the answer
1,000
Is 999 even or odd?
Show the answer
Odd
What is 999 + 10?
Show the answer
1,009
Practise with a game
Factors, Multiples & Primes
Multiples, factors, prime numbers, square numbers and prime factors.
Roman Numerals
Read and write Roman numerals from I to 3,999.Frequently asked questions
How do you write 999 in words?
999 is written "nine hundred and ninety-nine".
Is 999 a prime number?
No. 999 is a composite number, because it has more than two factors.
What are the factors of 999?
The factors of 999 are 1, 3, 9, 27, 37, 111, 333 and 999.
How do you write 999 in Roman numerals?
999 in Roman numerals is CMXCIX.