21,231 in words
21,231
twenty-one thousand two hundred thirty-one
21,231 is written twenty-one thousand two hundred thirty-one.
Ways to write it
- As an ordinal
- twenty-one thousand two hundred thirty-first
- Expanded form
- 20,000 + 1,000 + 200 + 30 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 2 | 200 |
| tens | 3 | 30 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 7, 9, 21, 63, 337, 1,011, 2,359, 3,033, 7,077 and 21,231 (12 factors)
- First 10 multiples
- 21,231, 42,462, 63,693, 84,924, 106,155, 127,386, 148,617, 169,848, 191,079, 212,310
- Square
- 21,231 × 21,231 = 450,755,361
- Square root
- ≈ 145.71
- Sum of the digits
- 2 + 1 + 2 + 3 + 1 = 9
- Rounded to the nearest 10
- 21,230
- Rounded to the nearest 100
- 21,200
- Rounded to the nearest 1000
- 21,000
- Number before
- 21,230
- Number after
- 21,232
- In binary
101001011101111
Quick check
What number comes just after 21,231?
Show the answer
21,232
Is 21,231 even or odd?
Show the answer
Odd
What is 21,231 + 10?
Show the answer
21,241
Practice with a game
Factors, Multiples & Primes
Multiples, factors, prime numbers, square numbers and prime factors.
Number Patterns
Find the missing number in a sequence.Frequently asked questions
How do you write 21,231 in words?
21,231 is written "twenty-one thousand two hundred thirty-one".
Is 21,231 a prime number?
No. 21,231 is a composite number, because it has more than two factors.
What are the factors of 21,231?
The factors of 21,231 are 1, 3, 7, 9, 21, 63, 337, 1,011, 2,359, 3,033, 7,077 and 21,231.