21,218 in words
21,218
twenty-one thousand two hundred eighteen
21,218 is written twenty-one thousand two hundred eighteen.
Ways to write it
- As an ordinal
- twenty-one thousand two hundred eighteenth
- Expanded form
- 20,000 + 1,000 + 200 + 10 + 8
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 2 | 200 |
| tens | 1 | 10 |
| ones | 8 | 8 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 1, 2, 103, 206, 10,609 and 21,218 (6 factors)
- First 10 multiples
- 21,218, 42,436, 63,654, 84,872, 106,090, 127,308, 148,526, 169,744, 190,962, 212,180
- Square
- 21,218 × 21,218 = 450,203,524
- Square root
- ≈ 145.66
- Sum of the digits
- 2 + 1 + 2 + 1 + 8 = 14
- Rounded to the nearest 10
- 21,220
- Rounded to the nearest 100
- 21,200
- Rounded to the nearest 1000
- 21,000
- Number before
- 21,217
- Number after
- 21,219
- In binary
101001011100010
Quick check
What number comes just after 21,218?
Show the answer
21,219
Is 21,218 even or odd?
Show the answer
Even
What is 21,218 + 10?
Show the answer
21,228
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 21,218 in words?
21,218 is written "twenty-one thousand two hundred eighteen".
Is 21,218 a prime number?
No. 21,218 is a composite number, because it has more than two factors.
What are the factors of 21,218?
The factors of 21,218 are 1, 2, 103, 206, 10,609 and 21,218.