321 in words
321
three hundred and twenty-one
321 is written three hundred and twenty-one.
Ways to write it
- As an ordinal
- three hundred and twenty-first
- Roman numeral
- CCCXXI
- Expanded form
- 300 + 20 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| hundreds | 3 | 300 |
| tens | 2 | 20 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 107 and 321 (4 factors)
- First 10 multiples
- 321, 642, 963, 1,284, 1,605, 1,926, 2,247, 2,568, 2,889, 3,210
- Square
- 321 × 321 = 1,03,041
- Square root
- ≈ 17.92
- Sum of the digits
- 3 + 2 + 1 = 6
- Rounded to the nearest 10
- 320
- Rounded to the nearest 100
- 300
- Number before
- 320
- Number after
- 322
- In binary
101000001
Quick check
What number comes just after 321?
Show the answer
322
Is 321 even or odd?
Show the answer
Odd
What is 321 + 10?
Show the answer
331
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 321 in words?
321 is written "three hundred and twenty-one".
Is 321 a prime number?
No. 321 is a composite number, because it has more than two factors.
What are the factors of 321?
The factors of 321 are 1, 3, 107 and 321.
How do you write 321 in Roman numerals?
321 in Roman numerals is CCCXXI.