21,100 in words
21,100
twenty-one thousand one hundred
21,100 is written twenty-one thousand one hundred.
Ways to write it
- As an ordinal
- twenty-one thousand one hundredth
- Expanded form
- 20,000 + 1,000 + 100
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 1 | 100 |
| tens | 0 | 0 |
| ones | 0 | 0 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 1, 2, 4, 5, 10, 20, 25, 50, 100, 211, 422, 844, 1,055, 2,110, 4,220, 5,275, 10,550 and 21,100 (18 factors)
- First 10 multiples
- 21,100, 42,200, 63,300, 84,400, 105,500, 126,600, 147,700, 168,800, 189,900, 211,000
- Square
- 21,100 × 21,100 = 445,210,000
- Square root
- ≈ 145.26
- Sum of the digits
- 2 + 1 + 1 + 0 + 0 = 4
- Rounded to the nearest 10
- 21,100
- Rounded to the nearest 100
- 21,100
- Rounded to the nearest 1000
- 21,000
- Number before
- 21,099
- Number after
- 21,101
- In binary
101001001101100
Quick check
What number comes just after 21,100?
Show the answer
21,101
Is 21,100 even or odd?
Show the answer
Even
What is 21,100 + 10?
Show the answer
21,110
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 21,100 in words?
21,100 is written "twenty-one thousand one hundred".
Is 21,100 a prime number?
No. 21,100 is a composite number, because it has more than two factors.
What are the factors of 21,100?
The factors of 21,100 are 1, 2, 4, 5, 10, 20, 25, 50, 100, 211, 422, 844, 1,055, 2,110, 4,220, 5,275, 10,550 and 21,100.