309 in words
309
three hundred and nine
309 is written three hundred and nine.
Ways to write it
- As an ordinal
- three hundred and ninth
- Roman numeral
- CCCIX
- Expanded form
- 300 + 9
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 3 | 300 |
| tens | 0 | 0 |
| ones | 9 | 9 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 103 and 309 (4 factors)
- First 10 multiples
- 309, 618, 927, 1,236, 1,545, 1,854, 2,163, 2,472, 2,781, 3,090
- Square
- 309 × 309 = 95,481
- Square root
- ≈ 17.58
- Sum of the digits
- 3 + 0 + 9 = 12
- Rounded to the nearest 10
- 310
- Rounded to the nearest 100
- 300
- Number before
- 308
- Number after
- 310
- In binary
100110101
Quick check
What number comes just after 309?
Show the answer
310
Is 309 even or odd?
Show the answer
Odd
What is 309 + 10?
Show the answer
319
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 309 in words?
309 is written "three hundred and nine".
Is 309 a prime number?
No. 309 is a composite number, because it has more than two factors.
What are the factors of 309?
The factors of 309 are 1, 3, 103 and 309.
How do you write 309 in Roman numerals?
309 in Roman numerals is CCCIX.