21,920 in words
21,920
twenty-one thousand nine hundred twenty
21,920 is written twenty-one thousand nine hundred twenty.
Ways to write it
- As an ordinal
- twenty-one thousand nine hundred twentieth
- Expanded form
- 20,000 + 1,000 + 900 + 20
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 9 | 900 |
| tens | 2 | 20 |
| ones | 0 | 0 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 80, 137, 160, 274, 548, 685, 1,096, 1,370, 2,192, 2,740, 4,384, 5,480, 10,960 and 21,920 (24 factors)
- First 10 multiples
- 21,920, 43,840, 65,760, 87,680, 109,600, 131,520, 153,440, 175,360, 197,280, 219,200
- Square
- 21,920 × 21,920 = 480,486,400
- Square root
- ≈ 148.05
- Sum of the digits
- 2 + 1 + 9 + 2 + 0 = 14
- Rounded to the nearest 10
- 21,920
- Rounded to the nearest 100
- 21,900
- Rounded to the nearest 1000
- 22,000
- Number before
- 21,919
- Number after
- 21,921
- In binary
101010110100000
Quick check
What number comes just after 21,920?
Show the answer
21,921
Is 21,920 even or odd?
Show the answer
Even
What is 21,920 + 10?
Show the answer
21,930
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 21,920 in words?
21,920 is written "twenty-one thousand nine hundred twenty".
Is 21,920 a prime number?
No. 21,920 is a composite number, because it has more than two factors.
What are the factors of 21,920?
The factors of 21,920 are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 80, 137, 160, 274, 548, 685, 1,096, 1,370, 2,192, 2,740, 4,384, 5,480, 10,960 and 21,920.