The number 22720
22720 is a composite number with 28 divisors. Its prime factorisation is × 5 × 71. Divisors (28): 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 71, 80, 142, 160, 284 … 22720.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
22720 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
22720 is composite. Its prime factorisation is
- 3
The divisors add up to 54864; without 22720 itself that is 32144, so 22720 is abundant (32144 is more than 22720). Euler's totient φ(22720) = 8960 numbers up to 22720 share no factor with it.
- 4
The digits of 22720 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 38 steps to reach 1.
LaTeX source of the formulas on this page
\[ 22720 = 2^{6} \times 5 \times 71 \]22720 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 28 |
| Sum of divisors | 54864 |
| Euler totient φ(n) | 8960 |
| Square | 516198400 |
| Cube | 11728027648000 |
| Square root | 150.731549 (= 8√355) |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 38 |
| Scientific notation | 2.272 × |
22720 in other forms
| Form | Value |
|---|---|
| In words | twenty-two thousand seven hundred and twenty |
| Binary (base 2) | 101100011000000 |
| Octal (base 8) | 54300 |
| Hexadecimal (base 16) | 58C0 |
| Base 3 | 1011011111 |
| As time | 22720 seconds = 6 h 18 min 40 s |
Is 22720 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (22720 ÷ 2 = 11360) | 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 (22720 ÷ 4 = 5680) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (22720 ÷ 5 = 4544) | 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 5) | 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 (22720 ÷ 8 = 2840) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (22720 ÷ 10 = 2272) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | 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 22720 a prime number?
No. 22720 = × 5 × 71, so it is divisible by 2.
What are the factors of 22720?
1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 71, 80, 142, 160, 284, 320, 355, 568, 710, 1136, 1420, 2272, 2840, 4544, 5680, 11360, 22720.
What is 22720 in binary?
101100011000000 (hexadecimal 58C0, octal 54300).
What is the square root of 22720?
About 150.7315, exactly 8√355.
Is 22720 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 22720?
It is a composite number with 28 divisors.