The number 15397
15397 is a composite number with 4 divisors. Its prime factorisation is 89 × 173. Divisors (4): 1, 89, 173, 15397.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 15397: a semiprime: 89 × 173, the product of two primes.
- 2
15397 is composite. Its prime factorisation is
- 3
The divisors add up to 15660; without 15397 itself that is 263, so 15397 is deficient (263 is less than 15397). Euler's totient φ(15397) = 15136 numbers up to 15397 share no factor with it.
- 4
The digits of 15397 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 133 steps to reach 1.
LaTeX source of the formulas on this page
\[ 15397 = 89 \times 173 \]
15397 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 15660 |
| Euler totient φ(n) | 15136 |
| Square | 237067609 |
| Cube | 3650129975773 |
| Square root | 124.084649 |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 133 |
| Scientific notation | 1.5397 × |
15397 in other forms
| Form | Value |
|---|---|
| In words | fifteen thousand three hundred and ninety-seven |
| Binary (base 2) | 11110000100101 |
| Octal (base 8) | 36045 |
| Hexadecimal (base 16) | 3C25 |
| Base 3 | 210010021 |
| As time | 15397 seconds = 4 h 16 min 37 s |
Is 15397 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 | No (remainder 2) | 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 | 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 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 15397 a prime number?
No. 15397 = 89 × 173, so it is divisible by 89.
What are the factors of 15397?
1, 89, 173, 15397.
What is 15397 in binary?
11110000100101 (hexadecimal 3C25, octal 36045).
What is the square root of 15397?
About 124.0846.
Is 15397 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 15397?
15397 is a semiprime: 89 × 173, the product of two primes.