The number 13231
13231 is a palindrome: it reads 13231 backwards too. Its prime factorisation is 101 × 131. Divisors (4): 1, 101, 131, 13231.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 13231: a palindrome: it reads 13231 backwards too; a semiprime: 101 × 131, the product of two primes.
- 2
13231 is composite. Its prime factorisation is
- 3
The divisors add up to 13464; without 13231 itself that is 233, so 13231 is deficient (233 is less than 13231). Euler's totient φ(13231) = 13000 numbers up to 13231 share no factor with it.
- 4
The digits of 13231 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 138 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13231 = 101 \times 131 \]
13231 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 13464 |
| Euler totient φ(n) | 13000 |
| Square | 175059361 |
| Cube | 2316210405391 |
| Square root | 115.026084 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 138 |
| Scientific notation | 1.3231 × |
13231 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand two hundred and thirty-one |
| Binary (base 2) | 11001110101111 |
| Octal (base 8) | 31657 |
| Hexadecimal (base 16) | 33AF |
| Base 3 | 200011001 |
| As time | 13231 seconds = 3 h 40 min 31 s |
Is 13231 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 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | 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 9) | 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 13231 a prime number?
No. 13231 = 101 × 131, so it is divisible by 101.
What are the factors of 13231?
1, 101, 131, 13231.
What is 13231 in binary?
11001110101111 (hexadecimal 33AF, octal 31657).
What is the square root of 13231?
About 115.0261.
Is 13231 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 13231?
13231 is a palindrome: it reads 13231 backwards too; a semiprime: 101 × 131, the product of two primes.