The number 15616
15616 is a composite number with 18 divisors. Its prime factorisation is × 61. Divisors (18): 1, 2, 4, 8, 16, 32, 61, 64, 122, 128, 244, 256, 488, 976, 1952, 3904 … 15616.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
15616 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
15616 is composite. Its prime factorisation is
- 3
The divisors add up to 31682; without 15616 itself that is 16066, so 15616 is abundant (16066 is more than 15616). Euler's totient φ(15616) = 7680 numbers up to 15616 share no factor with it.
- 4
The digits of 15616 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 27 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15616 = 2^{8} \times 61 \]15616 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 31682 |
| Euler totient φ(n) | 7680 |
| Square | 243859456 |
| Cube | 3808109264896 |
| Square root | 124.963995 (= 16√61) |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 27 |
| Scientific notation | 1.5616 × |
15616 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand six hundred and sixteen |
| Binary (base 2) | 11110100000000 |
| Octal (base 8) | 36400 |
| Hexadecimal (base 16) | 3D00 |
| Base 3 | 210102101 |
| As time | 15616 seconds = 4 h 20 min 16 s |
Is 15616 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (15616 ÷ 2 = 7808) | 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 | Yes (15616 ÷ 4 = 3904) | 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 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 | Yes (15616 ÷ 8 = 1952) | 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 6) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15616 a prime number?
No. 15616 = × 61, so it is divisible by 2.
What are the factors of 15616?
1, 2, 4, 8, 16, 32, 61, 64, 122, 128, 244, 256, 488, 976, 1952, 3904, 7808, 15616.
What is 15616 in binary?
11110100000000 (hexadecimal 3D00, octal 36400).
What is the square root of 15616?
About 124.9640, exactly 16√61.
Is 15616 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 15616?
It is a composite number with 18 divisors.