The number 31790
31790 is a composite number with 24 divisors. Its prime factorisation is 2 × 5 × 11 × . Divisors (24): 1, 2, 5, 10, 11, 17, 22, 34, 55, 85, 110, 170, 187, 289, 374, 578 … 31790.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31790 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31790 is composite. Its prime factorisation is
- 3
The divisors add up to 66312; without 31790 itself that is 34522, so 31790 is abundant (34522 is more than 31790). Euler's totient φ(31790) = 10880 numbers up to 31790 share no factor with it.
- 4
The digits of 31790 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31790 = 2 \times 5 \times 11 \times 17^{2} \]31790 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 66312 |
| Euler totient φ(n) | 10880 |
| Square | 1010604100 |
| Cube | 32127104339000 |
| Square root | 178.297504 (= 17√110) |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.179 × |
31790 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand seven hundred and ninety |
| Binary (base 2) | 111110000101110 |
| Octal (base 8) | 76056 |
| Hexadecimal (base 16) | 7C2E |
| Base 3 | 1121121102 |
| As time | 31790 seconds = 8 h 49 min 50 s |
Is 31790 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31790 ÷ 2 = 15895) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (31790 ÷ 5 = 6358) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 | No (remainder 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (31790 ÷ 10 = 3179) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (31790 ÷ 11 = 2890) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31790 a prime number?
No. 31790 = 2 × 5 × 11 × , so it is divisible by 2.
What are the factors of 31790?
1, 2, 5, 10, 11, 17, 22, 34, 55, 85, 110, 170, 187, 289, 374, 578, 935, 1445, 1870, 2890, 3179, 6358, 15895, 31790.
What is 31790 in binary?
111110000101110 (hexadecimal 7C2E, octal 76056).
What is the square root of 31790?
About 178.2975, exactly 17√110.
Is 31790 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 31790?
It is a composite number with 24 divisors.