The number 25001
25001 is a composite number with 4 divisors. Its prime factorisation is 23 × 1087. Divisors (4): 1, 23, 1087, 25001.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25001: a semiprime: 23 × 1087, the product of two primes.
- 2
25001 is composite. Its prime factorisation is
- 3
The divisors add up to 26112; without 25001 itself that is 1111, so 25001 is deficient (1111 is less than 25001). Euler's totient φ(25001) = 23892 numbers up to 25001 share no factor with it.
- 4
The digits of 25001 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 51 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25001 = 23 \times 1087 \]
25001 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 26112 |
| Euler totient φ(n) | 23892 |
| Square | 625050001 |
| Cube | 15626875075001 |
| Square root | 158.117045 |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 51 |
| Scientific notation | 2.5001 × |
25001 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand and one |
| Binary (base 2) | 110000110101001 |
| Octal (base 8) | 60651 |
| Hexadecimal (base 16) | 61A9 |
| Base 3 | 1021021222 |
| As time | 25001 seconds = 6 h 56 min 41 s |
Is 25001 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 2) | 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 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 5) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 25001 a prime number?
No. 25001 = 23 × 1087, so it is divisible by 23.
What are the factors of 25001?
1, 23, 1087, 25001.
What is 25001 in binary?
110000110101001 (hexadecimal 61A9, octal 60651).
What is the square root of 25001?
About 158.1170.
Is 25001 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 25001?
25001 is a semiprime: 23 × 1087, the product of two primes.