42,821 in words
42,821
forty-two thousand eight hundred and twenty-one
42,821 is written forty-two thousand eight hundred and twenty-one.
Ways to write it
- As an ordinal
- forty-two thousand eight hundred and twenty-first
- Expanded form
- 40,000 + 2,000 + 800 + 20 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 4 | 40,000 |
| thousands | 2 | 2,000 |
| hundreds | 8 | 800 |
| tens | 2 | 20 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Prime
- Factors
- 1 and 42,821 (2 factors)
- First 10 multiples
- 42,821, 85,642, 128,463, 171,284, 214,105, 256,926, 299,747, 342,568, 385,389, 428,210
- Square
- 42,821 × 42,821 = 1,833,638,041
- Square root
- ≈ 206.93
- Sum of the digits
- 4 + 2 + 8 + 2 + 1 = 17
- Rounded to the nearest 10
- 42,820
- Rounded to the nearest 100
- 42,800
- Rounded to the nearest 1000
- 43,000
- Number before
- 42,820
- Number after
- 42,822
- In binary
1010011101000101
Quick check
What number comes just after 42,821?
Show the answer
42,822
Is 42,821 even or odd?
Show the answer
Odd
What is 42,821 + 10?
Show the answer
42,831
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 42,821 in words?
42,821 is written "forty-two thousand eight hundred and twenty-one".
Is 42,821 a prime number?
Yes. 42,821 is a prime number: its only factors are 1 and 42,821.
What are the factors of 42,821?
The factors of 42,821 are 1 and 42,821.