The number 25442
25442 is a composite number with 4 divisors. Its prime factorisation is 2 × 12721. Divisors (4): 1, 2, 12721, 25442.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25442: a semiprime: 2 × 12721, the product of two primes.
- 2
25442 is composite. Its prime factorisation is
- 3
The divisors add up to 38166; without 25442 itself that is 12724, so 25442 is deficient (12724 is less than 25442). Euler's totient φ(25442) = 12720 numbers up to 25442 share no factor with it.
- 4
The digits of 25442 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 108 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25442 = 2 \times 12721 \]
25442 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 38166 |
| Euler totient φ(n) | 12720 |
| Square | 647295364 |
| Cube | 16468488650888 |
| Square root | 159.505486 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 108 |
| Scientific notation | 2.5442 × |
25442 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand four hundred and forty-two |
| Binary (base 2) | 110001101100010 |
| Octal (base 8) | 61542 |
| Hexadecimal (base 16) | 6362 |
| Base 3 | 1021220022 |
| As time | 25442 seconds = 7 h 4 min 2 s |
Is 25442 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (25442 ÷ 2 = 12721) | 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 2) | 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 2) | 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 2) | 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 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 25442 a prime number?
No. 25442 = 2 × 12721, so it is divisible by 2.
What are the factors of 25442?
1, 2, 12721, 25442.
What is 25442 in binary?
110001101100010 (hexadecimal 6362, octal 61542).
What is the square root of 25442?
About 159.5055.
Is 25442 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 25442?
25442 is a semiprime: 2 × 12721, the product of two primes.