The number 25909
25909 is a composite number with 4 divisors. Its prime factorisation is 13 × 1993. Divisors (4): 1, 13, 1993, 25909.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25909: a semiprime: 13 × 1993, the product of two primes.
- 2
25909 is composite. Its prime factorisation is
- 3
The divisors add up to 27916; without 25909 itself that is 2007, so 25909 is deficient (2007 is less than 25909). Euler's totient φ(25909) = 23904 numbers up to 25909 share no factor with it.
- 4
The digits of 25909 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 51 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25909 = 13 \times 1993 \]
25909 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 27916 |
| Euler totient φ(n) | 23904 |
| Square | 671276281 |
| Cube | 17392097164429 |
| Square root | 160.962729 |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 51 |
| Scientific notation | 2.5909 × |
25909 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand nine hundred and nine |
| Binary (base 2) | 110010100110101 |
| Octal (base 8) | 62465 |
| Hexadecimal (base 16) | 6535 |
| Base 3 | 1022112121 |
| As time | 25909 seconds = 7 h 11 min 49 s |
Is 25909 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 4) | 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 2) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | 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 25909 a prime number?
No. 25909 = 13 × 1993, so it is divisible by 13.
What are the factors of 25909?
1, 13, 1993, 25909.
What is 25909 in binary?
110010100110101 (hexadecimal 6535, octal 62465).
What is the square root of 25909?
About 160.9627.
Is 25909 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 25909?
25909 is a semiprime: 13 × 1993, the product of two primes.