The number 12985
12985 is a composite number with 12 divisors. Its prime factorisation is 5 × × 53. Divisors (12): 1, 5, 7, 35, 49, 53, 245, 265, 371, 1855, 2597, 12985.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
12985 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
12985 is composite. Its prime factorisation is
- 3
The divisors add up to 18468; without 12985 itself that is 5483, so 12985 is deficient (5483 is less than 12985). Euler's totient φ(12985) = 8736 numbers up to 12985 share no factor with it.
- 4
The digits of 12985 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 50 steps to reach 1.
LaTeX source of the formulas on this page
\[ 12985 = 5 \times 7^{2} \times 53 \]12985 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 18468 |
| Euler totient φ(n) | 8736 |
| Square | 168610225 |
| Cube | 2189403771625 |
| Square root | 113.951744 (= 7√265) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 50 |
| Scientific notation | 1.2985 × |
12985 in other forms
| Form | Value |
|---|---|
| In words | twelve thousand nine hundred and eighty-five |
| Binary (base 2) | 11001010111001 |
| Octal (base 8) | 31271 |
| Hexadecimal (base 16) | 32B9 |
| Base 3 | 122210221 |
| As time | 12985 seconds = 3 h 36 min 25 s |
Is 12985 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 (12985 ÷ 5 = 2597) | 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 (12985 ÷ 7 = 1855) | 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 5) | 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 12985 a prime number?
No. 12985 = 5 × × 53, so it is divisible by 5.
What are the factors of 12985?
1, 5, 7, 35, 49, 53, 245, 265, 371, 1855, 2597, 12985.
What is 12985 in binary?
11001010111001 (hexadecimal 32B9, octal 31271).
What is the square root of 12985?
About 113.9517, exactly 7√265.
Is 12985 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 12985?
It is a composite number with 12 divisors.