The number 15531
15531 is a composite number with 8 divisors. Its prime factorisation is 3 × 31 × 167. Divisors (8): 1, 3, 31, 93, 167, 501, 5177, 15531.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
15531 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
15531 is composite. Its prime factorisation is
- 3
The divisors add up to 21504; without 15531 itself that is 5973, so 15531 is deficient (5973 is less than 15531). Euler's totient φ(15531) = 9960 numbers up to 15531 share no factor with it.
- 4
The digits of 15531 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 146 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15531 = 3 \times 31 \times 167 \]
15531 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 21504 |
| Euler totient φ(n) | 9960 |
| Square | 241211961 |
| Cube | 3746262966291 |
| Square root | 124.623433 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 146 |
| Scientific notation | 1.5531 × |
15531 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand five hundred and thirty-one |
| Binary (base 2) | 11110010101011 |
| Octal (base 8) | 36253 |
| Hexadecimal (base 16) | 3CAB |
| Base 3 | 210022020 |
| As time | 15531 seconds = 4 h 18 min 51 s |
Is 15531 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 (15531 ÷ 3 = 5177) | 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 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 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 10) | 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 15531 a prime number?
No. 15531 = 3 × 31 × 167, so it is divisible by 3.
What are the factors of 15531?
1, 3, 31, 93, 167, 501, 5177, 15531.
What is 15531 in binary?
11110010101011 (hexadecimal 3CAB, octal 36253).
What is the square root of 15531?
About 124.6234.
Is 15531 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 15531?
It is a composite number with 8 divisors.