The number 18131
18131 is a twin prime (18131 and 18133 are both prime) and the 2078th prime number. Its only divisors are 1 and 18131.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18131: a twin prime (18131 and 18133 are both prime); the 2078th prime number.
- 2
18131 is prime, so its only factors are 1 and 18131. It is the 2078th prime; the next prime is 18133 and the one before is 18127.
- 3
The divisors add up to 18132; without 18131 itself that is 1, so 18131 is deficient (1 is less than 18131). Euler's totient φ(18131) = 18130 numbers up to 18131 share no factor with it.
- 4
The digits of 18131 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 123 steps to reach 1.
18131 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 18132 |
| Euler totient φ(n) | 18130 |
| Square | 328733161 |
| Cube | 5960260942091 |
| Square root | 134.651402 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 123 |
| Scientific notation | 1.8131 × |
18131 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand one hundred and thirty-one |
| Binary (base 2) | 100011011010011 |
| Octal (base 8) | 43323 |
| Hexadecimal (base 16) | 46D3 |
| Base 3 | 220212112 |
| As time | 18131 seconds = 5 h 2 min 11 s |
Is 18131 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 1) | 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 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 3) | 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 18131 a prime number?
Yes. 18131 is divisible only by 1 and itself.
What are the factors of 18131?
1, 18131.
What is 18131 in binary?
100011011010011 (hexadecimal 46D3, octal 43323).
What is the square root of 18131?
About 134.6514.
Is 18131 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 18131?
18131 is a twin prime (18131 and 18133 are both prime); the 2078th prime number.