21,824 in words
21,824
twenty-one thousand eight hundred twenty-four
21,824 is written twenty-one thousand eight hundred twenty-four.
Ways to write it
- As an ordinal
- twenty-one thousand eight hundred twenty-fourth
- Expanded form
- 20,000 + 1,000 + 800 + 20 + 4
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 8 | 800 |
| tens | 2 | 20 |
| ones | 4 | 4 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 1, 2, 4, 8, 11, 16, 22, 31, 32, 44, 62, 64, 88, 124, 176, 248, 341, 352, 496, 682, 704, 992, 1,364, 1,984, 2,728, 5,456, 10,912 and 21,824 (28 factors)
- First 10 multiples
- 21,824, 43,648, 65,472, 87,296, 109,120, 130,944, 152,768, 174,592, 196,416, 218,240
- Square
- 21,824 × 21,824 = 476,286,976
- Square root
- ≈ 147.73
- Sum of the digits
- 2 + 1 + 8 + 2 + 4 = 17
- Rounded to the nearest 10
- 21,820
- Rounded to the nearest 100
- 21,800
- Rounded to the nearest 1000
- 22,000
- Number before
- 21,823
- Number after
- 21,825
- In binary
101010101000000
Quick check
What number comes just after 21,824?
Show the answer
21,825
Is 21,824 even or odd?
Show the answer
Even
What is 21,824 + 10?
Show the answer
21,834
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 21,824 in words?
21,824 is written "twenty-one thousand eight hundred twenty-four".
Is 21,824 a prime number?
No. 21,824 is a composite number, because it has more than two factors.
What are the factors of 21,824?
The factors of 21,824 are 1, 2, 4, 8, 11, 16, 22, 31, 32, 44, 62, 64, 88, 124, 176, 248, 341, 352, 496, 682, 704, 992, 1,364, 1,984, 2,728, 5,456, 10,912 and 21,824.