The number 31608
31608 is a composite number with 24 divisors. Its prime factorisation is × × 439. Divisors (24): 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72, 439, 878, 1317, 1756 … 31608.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31608: a Harshad number: divisible by its digit sum 18.
- 2
31608 is composite. Its prime factorisation is
- 3
The divisors add up to 85800; without 31608 itself that is 54192, so 31608 is abundant (54192 is more than 31608). Euler's totient φ(31608) = 10512 numbers up to 31608 share no factor with it.
- 4
The digits of 31608 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 77 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31608 = 2^{3} \times 3^{2} \times 439 \]31608 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 85800 |
| Euler totient φ(n) | 10512 |
| Square | 999065664 |
| Cube | 31578467507712 |
| Square root | 177.786389 (= 6√878) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 77 |
| Scientific notation | 3.1608 × |
31608 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand six hundred and eight |
| Binary (base 2) | 111101101111000 |
| Octal (base 8) | 75570 |
| Hexadecimal (base 16) | 7B78 |
| Base 3 | 1121100200 |
| As time | 31608 seconds = 8 h 46 min 48 s |
Is 31608 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31608 ÷ 2 = 15804) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (31608 ÷ 3 = 10536) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (31608 ÷ 4 = 7902) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (31608 ÷ 6 = 5268) | 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 | Yes (31608 ÷ 8 = 3951) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (31608 ÷ 9 = 3512) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | 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 | Yes (31608 ÷ 12 = 2634) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31608 a prime number?
No. 31608 = × × 439, so it is divisible by 2.
What are the factors of 31608?
1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72, 439, 878, 1317, 1756, 2634, 3512, 3951, 5268, 7902, 10536, 15804, 31608.
What is 31608 in binary?
111101101111000 (hexadecimal 7B78, octal 75570).
What is the square root of 31608?
About 177.7864, exactly 6√878.
Is 31608 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 31608?
31608 is a Harshad number: divisible by its digit sum 18.