21,000 in words
21,000
twenty-one thousand
21,000 is written twenty-one thousand.
Ways to write it
- As an ordinal
- twenty-one thousandth
- Expanded form
- 20,000 + 1,000
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 0 | 0 |
| tens | 0 | 0 |
| ones | 0 | 0 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 64 factors: too many to list
- First 10 multiples
- 21,000, 42,000, 63,000, 84,000, 105,000, 126,000, 147,000, 168,000, 189,000, 210,000
- Square
- 21,000 × 21,000 = 441,000,000
- Square root
- ≈ 144.91
- Sum of the digits
- 2 + 1 + 0 + 0 + 0 = 3
- Rounded to the nearest 10
- 21,000
- Rounded to the nearest 100
- 21,000
- Rounded to the nearest 1000
- 21,000
- Number before
- 20,999
- Number after
- 21,001
- In binary
101001000001000
Quick check
What number comes just after 21,000?
Show the answer
21,001
Is 21,000 even or odd?
Show the answer
Even
What is 21,000 + 10?
Show the answer
21,010
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 21,000 in words?
21,000 is written "twenty-one thousand".
Is 21,000 a prime number?
No. 21,000 is a composite number, because it has more than two factors.