The number 21160
21160 is a composite number with 24 divisors. Its prime factorisation is × 5 × . Divisors (24): 1, 2, 4, 5, 8, 10, 20, 23, 40, 46, 92, 115, 184, 230, 460, 529 … 21160.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21160: a Harshad number: divisible by its digit sum 10.
- 2
21160 is composite. Its prime factorisation is
- 3
The divisors add up to 49770; without 21160 itself that is 28610, so 21160 is abundant (28610 is more than 21160). Euler's totient φ(21160) = 8096 numbers up to 21160 share no factor with it.
- 4
The digits of 21160 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 118 steps to reach 1.
LaTeX source of the formulas on this page
\[ 21160 = 2^{3} \times 5 \times 23^{2} \]21160 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 49770 |
| Euler totient φ(n) | 8096 |
| Square | 447745600 |
| Cube | 9474296896000 |
| Square root | 145.464772 (= 46√10) |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 118 |
| Scientific notation | 2.116 × |
21160 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand one hundred and sixty |
| Binary (base 2) | 101001010101000 |
| Octal (base 8) | 51250 |
| Hexadecimal (base 16) | 52A8 |
| Base 3 | 1002000201 |
| As time | 21160 seconds = 5 h 52 min 40 s |
Is 21160 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (21160 ÷ 2 = 10580) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (21160 ÷ 4 = 5290) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (21160 ÷ 5 = 4232) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | Yes (21160 ÷ 8 = 2645) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (21160 ÷ 10 = 2116) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21160 a prime number?
No. 21160 = × 5 × , so it is divisible by 2.
What are the factors of 21160?
1, 2, 4, 5, 8, 10, 20, 23, 40, 46, 92, 115, 184, 230, 460, 529, 920, 1058, 2116, 2645, 4232, 5290, 10580, 21160.
What is 21160 in binary?
101001010101000 (hexadecimal 52A8, octal 51250).
What is the square root of 21160?
About 145.4648, exactly 46√10.
Is 21160 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 21160?
21160 is a Harshad number: divisible by its digit sum 10.