The number 18331
18331 is a composite number with 4 divisors. Its prime factorisation is 23 × 797. Divisors (4): 1, 23, 797, 18331.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18331: a semiprime: 23 × 797, the product of two primes.
- 2
18331 is composite. Its prime factorisation is
- 3
The divisors add up to 19152; without 18331 itself that is 821, so 18331 is deficient (821 is less than 18331). Euler's totient φ(18331) = 17512 numbers up to 18331 share no factor with it.
- 4
The digits of 18331 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 92 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18331 = 23 \times 797 \]
18331 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 19152 |
| Euler totient φ(n) | 17512 |
| Square | 336025561 |
| Cube | 6159684558691 |
| Square root | 135.392023 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 92 |
| Scientific notation | 1.8331 × |
18331 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand three hundred and thirty-one |
| Binary (base 2) | 100011110011011 |
| Octal (base 8) | 43633 |
| Hexadecimal (base 16) | 479B |
| Base 3 | 221010221 |
| As time | 18331 seconds = 5 h 5 min 31 s |
Is 18331 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 1) | 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 1) | 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 | No (remainder 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | 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 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18331 a prime number?
No. 18331 = 23 × 797, so it is divisible by 23.
What are the factors of 18331?
1, 23, 797, 18331.
What is 18331 in binary?
100011110011011 (hexadecimal 479B, octal 43633).
What is the square root of 18331?
About 135.3920.
Is 18331 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 18331?
18331 is a semiprime: 23 × 797, the product of two primes.