21,221 in words
21,221
twenty-one thousand two hundred and twenty-one
21,221 is written twenty-one thousand two hundred and twenty-one.
Ways to write it
- As an ordinal
- twenty-one thousand two hundred and twenty-first
- Expanded form
- 20,000 + 1,000 + 200 + 20 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 2 | 200 |
| tens | 2 | 20 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Prime
- Factors
- 1 and 21,221 (2 factors)
- First 10 multiples
- 21,221, 42,442, 63,663, 84,884, 106,105, 127,326, 148,547, 169,768, 190,989, 212,210
- Square
- 21,221 × 21,221 = 450,330,841
- Square root
- ≈ 145.67
- Sum of the digits
- 2 + 1 + 2 + 2 + 1 = 8
- Rounded to the nearest 10
- 21,220
- Rounded to the nearest 100
- 21,200
- Rounded to the nearest 1000
- 21,000
- Number before
- 21,220
- Number after
- 21,222
- In binary
101001011100101
Quick check
What number comes just after 21,221?
Show the answer
21,222
Is 21,221 even or odd?
Show the answer
Odd
What is 21,221 + 10?
Show the answer
21,231
Practise 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 21,221 in words?
21,221 is written "twenty-one thousand two hundred and twenty-one".
Is 21,221 a prime number?
Yes. 21,221 is a prime number: its only factors are 1 and 21,221.
What are the factors of 21,221?
The factors of 21,221 are 1 and 21,221.