The number 31631
31631 is a composite number with 4 divisors. Its prime factorisation is 47 × 673. Divisors (4): 1, 47, 673, 31631.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31631: a semiprime: 47 × 673, the product of two primes.
- 2
31631 is composite. Its prime factorisation is
- 3
The divisors add up to 32352; without 31631 itself that is 721, so 31631 is deficient (721 is less than 31631). Euler's totient φ(31631) = 30912 numbers up to 31631 share no factor with it.
- 4
The digits of 31631 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 178 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31631 = 47 \times 673 \]
31631 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 32352 |
| Euler totient φ(n) | 30912 |
| Square | 1000520161 |
| Cube | 31647453212591 |
| Square root | 177.851061 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 178 |
| Scientific notation | 3.1631 × |
31631 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand six hundred and thirty-one |
| Binary (base 2) | 111101110001111 |
| Octal (base 8) | 75617 |
| Hexadecimal (base 16) | 7B8F |
| Base 3 | 1121101112 |
| As time | 31631 seconds = 8 h 47 min 11 s |
Is 31631 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | 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 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 | No (remainder 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31631 a prime number?
No. 31631 = 47 × 673, so it is divisible by 47.
What are the factors of 31631?
1, 47, 673, 31631.
What is 31631 in binary?
111101110001111 (hexadecimal 7B8F, octal 75617).
What is the square root of 31631?
About 177.8511.
Is 31631 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 31631?
31631 is a semiprime: 47 × 673, the product of two primes.