The number 13615
13615 is a composite number with 8 divisors. Its prime factorisation is 5 × 7 × 389. Divisors (8): 1, 5, 7, 35, 389, 1945, 2723, 13615.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
13615 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
13615 is composite. Its prime factorisation is
- 3
The divisors add up to 18720; without 13615 itself that is 5105, so 13615 is deficient (5105 is less than 13615). Euler's totient φ(13615) = 9312 numbers up to 13615 share no factor with it.
- 4
The digits of 13615 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 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 13615 = 5 \times 7 \times 389 \]
13615 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 18720 |
| Euler totient φ(n) | 9312 |
| Square | 185368225 |
| Cube | 2523788383375 |
| Square root | 116.683332 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 89 |
| Scientific notation | 1.3615 × |
13615 in other forms
| Form | Value |
|---|---|
| In words | thirteen thousand six hundred and fifteen |
| Binary (base 2) | 11010100101111 |
| Octal (base 8) | 32457 |
| Hexadecimal (base 16) | 352F |
| Base 3 | 200200021 |
| As time | 13615 seconds = 3 h 46 min 55 s |
Is 13615 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 | Yes (13615 ÷ 5 = 2723) | 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 (13615 ÷ 7 = 1945) | 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 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 8) | 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 13615 a prime number?
No. 13615 = 5 × 7 × 389, so it is divisible by 5.
What are the factors of 13615?
1, 5, 7, 35, 389, 1945, 2723, 13615.
What is 13615 in binary?
11010100101111 (hexadecimal 352F, octal 32457).
What is the square root of 13615?
About 116.6833.
Is 13615 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 13615?
It is a composite number with 8 divisors.