21,829 in words
21,829
twenty-one thousand eight hundred and twenty-nine
21,829 is written twenty-one thousand eight hundred and twenty-nine.
Ways to write it
- As an ordinal
- twenty-one thousand eight hundred and twenty-ninth
- Expanded form
- 20,000 + 1,000 + 800 + 20 + 9
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 8 | 800 |
| tens | 2 | 20 |
| ones | 9 | 9 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 83, 263 and 21,829 (4 factors)
- First 10 multiples
- 21,829, 43,658, 65,487, 87,316, 109,145, 130,974, 152,803, 174,632, 196,461, 218,290
- Square
- 21,829 × 21,829 = 476,505,241
- Square root
- ≈ 147.75
- Sum of the digits
- 2 + 1 + 8 + 2 + 9 = 22
- Rounded to the nearest 10
- 21,830
- Rounded to the nearest 100
- 21,800
- Rounded to the nearest 1000
- 22,000
- Number before
- 21,828
- Number after
- 21,830
- In binary
101010101000101
Quick check
What number comes just after 21,829?
Show the answer
21,830
Is 21,829 even or odd?
Show the answer
Odd
What is 21,829 + 10?
Show the answer
21,839
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 21,829 in words?
21,829 is written "twenty-one thousand eight hundred and twenty-nine".
Is 21,829 a prime number?
No. 21,829 is a composite number, because it has more than two factors.
What are the factors of 21,829?
The factors of 21,829 are 1, 83, 263 and 21,829.