The number 15505
15505 is a composite number with 8 divisors. Its prime factorisation is 5 × 7 × 443. Divisors (8): 1, 5, 7, 35, 443, 2215, 3101, 15505.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
15505 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
15505 is composite. Its prime factorisation is
- 3
The divisors add up to 21312; without 15505 itself that is 5807, so 15505 is deficient (5807 is less than 15505). Euler's totient φ(15505) = 10608 numbers up to 15505 share no factor with it.
- 4
The digits of 15505 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 146 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15505 = 5 \times 7 \times 443 \]
15505 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 21312 |
| Euler totient φ(n) | 10608 |
| Square | 240405025 |
| Cube | 3727479912625 |
| Square root | 124.519075 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 146 |
| Scientific notation | 1.5505 × |
15505 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand five hundred and five |
| Binary (base 2) | 11110010010001 |
| Octal (base 8) | 36221 |
| Hexadecimal (base 16) | 3C91 |
| Base 3 | 210021021 |
| As time | 15505 seconds = 4 h 18 min 25 s |
Is 15505 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 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (15505 ÷ 5 = 3101) | 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 | Yes (15505 ÷ 7 = 2215) | 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 1) | 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 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15505 a prime number?
No. 15505 = 5 × 7 × 443, so it is divisible by 5.
What are the factors of 15505?
1, 5, 7, 35, 443, 2215, 3101, 15505.
What is 15505 in binary?
11110010010001 (hexadecimal 3C91, octal 36221).
What is the square root of 15505?
About 124.5191.
Is 15505 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 15505?
It is a composite number with 8 divisors.