The number 47931
47931 is a composite number with 8 divisors. Its prime factorisation is 3 × 13 × 1229. Divisors (8): 1, 3, 13, 39, 1229, 3687, 15977, 47931.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
47931 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
47931 is composite. Its prime factorisation is
- 3
The divisors add up to 68880; without 47931 itself that is 20949, so 47931 is deficient (20949 is less than 47931). Euler's totient φ(47931) = 29472 numbers up to 47931 share no factor with it.
- 4
The digits of 47931 add up to 24, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 96 steps to reach 1.
LaTeX source of the formulas on this page
\[ 47931 = 3 \times 13 \times 1229 \]
47931 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 68880 |
| Euler totient φ(n) | 29472 |
| Square | 2297380761 |
| Cube | 110115757255491 |
| Square root | 218.931496 |
| Digit sum / digital root | 24 / 6 |
| Collatz steps to 1 | 96 |
| Scientific notation | 4.7931 × |
47931 in other forms
| Form | Value |
|---|---|
| In words | forty-seven thousand nine hundred and thirty-one |
| Binary (base 2) | 1011101100111011 |
| Octal (base 8) | 135473 |
| Hexadecimal (base 16) | BB3B |
| Base 3 | 2102202020 |
| As time | 47931 seconds = 13 h 18 min 51 s |
Is 47931 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 | Yes (47931 ÷ 3 = 15977) | 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 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 47931 a prime number?
No. 47931 = 3 × 13 × 1229, so it is divisible by 3.
What are the factors of 47931?
1, 3, 13, 39, 1229, 3687, 15977, 47931.
What is 47931 in binary?
1011101100111011 (hexadecimal BB3B, octal 135473).
What is the square root of 47931?
About 218.9315.
Is 47931 divisible by 3?
Yes. Its digits add up to 24, a multiple of 3.
What is special about the number 47931?
It is a composite number with 8 divisors.