The number 25742
25742 is a composite number with 8 divisors. Its prime factorisation is 2 × 61 × 211. Divisors (8): 1, 2, 61, 122, 211, 422, 12871, 25742.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
25742 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
25742 is composite. Its prime factorisation is
- 3
The divisors add up to 39432; without 25742 itself that is 13690, so 25742 is deficient (13690 is less than 25742). Euler's totient φ(25742) = 12600 numbers up to 25742 share no factor with it.
- 4
The digits of 25742 add up to 20, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 170 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25742 = 2 \times 61 \times 211 \]
25742 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 39432 |
| Euler totient φ(n) | 12600 |
| Square | 662650564 |
| Cube | 17057950818488 |
| Square root | 160.443136 |
| Digit sum / digital root | 20 / 2 |
| Collatz steps to 1 | 170 |
| Scientific notation | 2.5742 × |
25742 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand seven hundred and forty-two |
| Binary (base 2) | 110010010001110 |
| Octal (base 8) | 62216 |
| Hexadecimal (base 16) | 648E |
| Base 3 | 1022022102 |
| As time | 25742 seconds = 7 h 9 min 2 s |
Is 25742 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (25742 ÷ 2 = 12871) | 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 3) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | 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 2) | 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 25742 a prime number?
No. 25742 = 2 × 61 × 211, so it is divisible by 2.
What are the factors of 25742?
1, 2, 61, 122, 211, 422, 12871, 25742.
What is 25742 in binary?
110010010001110 (hexadecimal 648E, octal 62216).
What is the square root of 25742?
About 160.4431.
Is 25742 divisible by 3?
No. Its digits add up to 20, which is not a multiple of 3.
What is special about the number 25742?
It is a composite number with 8 divisors.