The number 15509
15509 is a composite number with 4 divisors. Its prime factorisation is 13 × 1193. Divisors (4): 1, 13, 1193, 15509.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 15509: a semiprime: 13 × 1193, the product of two primes.
- 2
15509 is composite. Its prime factorisation is
- 3
The divisors add up to 16716; without 15509 itself that is 1207, so 15509 is deficient (1207 is less than 15509). Euler's totient φ(15509) = 14304 numbers up to 15509 share no factor with it.
- 4
The digits of 15509 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 53 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15509 = 13 \times 1193 \]
15509 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 16716 |
| Euler totient φ(n) | 14304 |
| Square | 240529081 |
| Cube | 3730365517229 |
| Square root | 124.535136 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 53 |
| Scientific notation | 1.5509 × |
15509 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand five hundred and nine |
| Binary (base 2) | 11110010010101 |
| Octal (base 8) | 36225 |
| Hexadecimal (base 16) | 3C95 |
| Base 3 | 210021102 |
| As time | 15509 seconds = 4 h 18 min 29 s |
Is 15509 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 4) | 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 4) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15509 a prime number?
No. 15509 = 13 × 1193, so it is divisible by 13.
What are the factors of 15509?
1, 13, 1193, 15509.
What is 15509 in binary?
11110010010101 (hexadecimal 3C95, octal 36225).
What is the square root of 15509?
About 124.5351.
Is 15509 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 15509?
15509 is a semiprime: 13 × 1193, the product of two primes.