21,420 in words
21,420
twenty-one thousand four hundred twenty
21,420 is written twenty-one thousand four hundred twenty.
Ways to write it
- As an ordinal
- twenty-one thousand four hundred twentieth
- Expanded form
- 20,000 + 1,000 + 400 + 20
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 2 | 20,000 |
| thousands | 1 | 1,000 |
| hundreds | 4 | 400 |
| tens | 2 | 20 |
| ones | 0 | 0 |
Number facts
- Even or odd
- Even
- Prime or composite
- Composite
- Factors
- 72 factors: too many to list
- First 10 multiples
- 21,420, 42,840, 64,260, 85,680, 107,100, 128,520, 149,940, 171,360, 192,780, 214,200
- Square
- 21,420 × 21,420 = 458,816,400
- Square root
- ≈ 146.36
- Sum of the digits
- 2 + 1 + 4 + 2 + 0 = 9
- Rounded to the nearest 10
- 21,420
- Rounded to the nearest 100
- 21,400
- Rounded to the nearest 1000
- 21,000
- Number before
- 21,419
- Number after
- 21,421
- In binary
101001110101100
Quick check
What number comes just after 21,420?
Show the answer
21,421
Is 21,420 even or odd?
Show the answer
Even
What is 21,420 + 10?
Show the answer
21,430
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 21,420 in words?
21,420 is written "twenty-one thousand four hundred twenty".
Is 21,420 a prime number?
No. 21,420 is a composite number, because it has more than two factors.