The number 23831
23831 is a twin prime (23831 and 23833 are both prime) and the 2651st prime number. Its only divisors are 1 and 23831.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 23831: a twin prime (23831 and 23833 are both prime); the 2651st prime number.
- 2
23831 is prime, so its only factors are 1 and 23831. It is the 2651st prime; the next prime is 23833 and the one before is 23827.
- 3
The divisors add up to 23832; without 23831 itself that is 1, so 23831 is deficient (1 is less than 23831). Euler's totient φ(23831) = 23830 numbers up to 23831 share no factor with it.
- 4
The digits of 23831 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 144 steps to reach 1.
23831 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 23832 |
| Euler totient φ(n) | 23830 |
| Square | 567916561 |
| Cube | 13534019565191 |
| Square root | 154.372925 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 144 |
| Scientific notation | 2.3831 × |
23831 in other forms
| Form | Value |
|---|---|
| In words | twenty-three thousand eight hundred and thirty-one |
| Binary (base 2) | 101110100010111 |
| Octal (base 8) | 56427 |
| Hexadecimal (base 16) | 5D17 |
| Base 3 | 1012200122 |
| As time | 23831 seconds = 6 h 37 min 11 s |
Is 23831 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 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 | No (remainder 7) | 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 1) | 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 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 23831 a prime number?
Yes. 23831 is divisible only by 1 and itself.
What are the factors of 23831?
1, 23831.
What is 23831 in binary?
101110100010111 (hexadecimal 5D17, octal 56427).
What is the square root of 23831?
About 154.3729.
Is 23831 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 23831?
23831 is a twin prime (23831 and 23833 are both prime); the 2651st prime number.