The number 25009
25009 is a composite number with 4 divisors. Its prime factorisation is 89 × 281. Divisors (4): 1, 89, 281, 25009.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25009: a semiprime: 89 × 281, the product of two primes.
- 2
25009 is composite. Its prime factorisation is
- 3
The divisors add up to 25380; without 25009 itself that is 371, so 25009 is deficient (371 is less than 25009). Euler's totient φ(25009) = 24640 numbers up to 25009 share no factor with it.
- 4
The digits of 25009 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 157 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25009 = 89 \times 281 \]
25009 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 25380 |
| Euler totient φ(n) | 24640 |
| Square | 625450081 |
| Cube | 15641881075729 |
| Square root | 158.142341 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 157 |
| Scientific notation | 2.5009 × |
25009 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand and nine |
| Binary (base 2) | 110000110110001 |
| Octal (base 8) | 60661 |
| Hexadecimal (base 16) | 61B1 |
| Base 3 | 1021022021 |
| As time | 25009 seconds = 6 h 56 min 49 s |
Is 25009 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 5) | 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 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | 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 25009 a prime number?
No. 25009 = 89 × 281, so it is divisible by 89.
What are the factors of 25009?
1, 89, 281, 25009.
What is 25009 in binary?
110000110110001 (hexadecimal 61B1, octal 60661).
What is the square root of 25009?
About 158.1423.
Is 25009 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 25009?
25009 is a semiprime: 89 × 281, the product of two primes.