The number 31625
31625 is a composite number with 16 divisors. Its prime factorisation is × 11 × 23. Divisors (16): 1, 5, 11, 23, 25, 55, 115, 125, 253, 275, 575, 1265, 1375, 2875, 6325, 31625.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31625 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31625 is composite. Its prime factorisation is
- 3
The divisors add up to 44928; without 31625 itself that is 13303, so 31625 is deficient (13303 is less than 31625). Euler's totient φ(31625) = 22000 numbers up to 31625 share no factor with it.
- 4
The digits of 31625 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31625 = 5^{3} \times 11 \times 23 \]31625 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 44928 |
| Euler totient φ(n) | 22000 |
| Square | 1000140625 |
| Cube | 31629447265625 |
| Square root | 177.834192 (= 5√1265) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1625 × |
31625 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand six hundred and twenty-five |
| Binary (base 2) | 111101110001001 |
| Octal (base 8) | 75611 |
| Hexadecimal (base 16) | 7B89 |
| Base 3 | 1121101022 |
| As time | 31625 seconds = 8 h 47 min 5 s |
Is 31625 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (31625 ÷ 5 = 6325) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | 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 | No (remainder 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (31625 ÷ 11 = 2875) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31625 a prime number?
No. 31625 = × 11 × 23, so it is divisible by 5.
What are the factors of 31625?
1, 5, 11, 23, 25, 55, 115, 125, 253, 275, 575, 1265, 1375, 2875, 6325, 31625.
What is 31625 in binary?
111101110001001 (hexadecimal 7B89, octal 75611).
What is the square root of 31625?
About 177.8342, exactly 5√1265.
Is 31625 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 31625?
It is a composite number with 16 divisors.