16,821 in words
16,821
sixteen thousand eight hundred and twenty-one
16,821 is written sixteen thousand eight hundred and twenty-one.
Ways to write it
- As an ordinal
- sixteen thousand eight hundred and twenty-first
- Expanded form
- 10,000 + 6,000 + 800 + 20 + 1
Place value
| Place | Digit | Value |
|---|---|---|
| ten thousands | 1 | 10,000 |
| thousands | 6 | 6,000 |
| hundreds | 8 | 800 |
| tens | 2 | 20 |
| ones | 1 | 1 |
Number facts
- Even or odd
- Odd
- Prime or composite
- Composite
- Factors
- 1, 3, 7, 9, 21, 27, 63, 89, 189, 267, 623, 801, 1,869, 2,403, 5,607 and 16,821 (16 factors)
- First 10 multiples
- 16,821, 33,642, 50,463, 67,284, 84,105, 100,926, 117,747, 134,568, 151,389, 168,210
- Square
- 16,821 × 16,821 = 282,946,041
- Square root
- ≈ 129.70
- Sum of the digits
- 1 + 6 + 8 + 2 + 1 = 18
- Rounded to the nearest 10
- 16,820
- Rounded to the nearest 100
- 16,800
- Rounded to the nearest 1000
- 17,000
- Number before
- 16,820
- Number after
- 16,822
- In binary
100000110110101
Quick check
What number comes just after 16,821?
Show the answer
16,822
Is 16,821 even or odd?
Show the answer
Odd
What is 16,821 + 10?
Show the answer
16,831
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 16,821 in words?
16,821 is written "sixteen thousand eight hundred and twenty-one".
Is 16,821 a prime number?
No. 16,821 is a composite number, because it has more than two factors.
What are the factors of 16,821?
The factors of 16,821 are 1, 3, 7, 9, 21, 27, 63, 89, 189, 267, 623, 801, 1,869, 2,403, 5,607 and 16,821.