The number 31904
31904 is a composite number with 12 divisors. Its prime factorisation is × 997. Divisors (12): 1, 2, 4, 8, 16, 32, 997, 1994, 3988, 7976, 15952, 31904.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
31904 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
31904 is composite. Its prime factorisation is
- 3
The divisors add up to 62874; without 31904 itself that is 30970, so 31904 is deficient (30970 is less than 31904). Euler's totient φ(31904) = 15936 numbers up to 31904 share no factor with it.
- 4
The digits of 31904 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 54 steps to reach 1.
LaTeX source of the formulas on this page
\[ 31904 = 2^{5} \times 997 \]31904 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 62874 |
| Euler totient φ(n) | 15936 |
| Square | 1017865216 |
| Cube | 32473971851264 |
| Square root | 178.616908 (= 4√1994) |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 54 |
| Scientific notation | 3.1904 × |
31904 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand nine hundred and four |
| Binary (base 2) | 111110010100000 |
| Octal (base 8) | 76240 |
| Hexadecimal (base 16) | 7CA0 |
| Base 3 | 1121202122 |
| As time | 31904 seconds = 8 h 51 min 44 s |
Is 31904 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (31904 ÷ 2 = 15952) | 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 | Yes (31904 ÷ 4 = 7976) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 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 (31904 ÷ 8 = 3988) | 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 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 31904 a prime number?
No. 31904 = × 997, so it is divisible by 2.
What are the factors of 31904?
1, 2, 4, 8, 16, 32, 997, 1994, 3988, 7976, 15952, 31904.
What is 31904 in binary?
111110010100000 (hexadecimal 7CA0, octal 76240).
What is the square root of 31904?
About 178.6169, exactly 4√1994.
Is 31904 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 31904?
It is a composite number with 12 divisors.