The number 25989
25989 is a composite number with 4 divisors. Its prime factorisation is 3 × 8663. Divisors (4): 1, 3, 8663, 25989.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25989: a semiprime: 3 × 8663, the product of two primes.
- 2
25989 is composite. Its prime factorisation is
- 3
The divisors add up to 34656; without 25989 itself that is 8667, so 25989 is deficient (8667 is less than 25989). Euler's totient φ(25989) = 17324 numbers up to 25989 share no factor with it.
- 4
The digits of 25989 add up to 33, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 126 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25989 = 3 \times 8663 \]
25989 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 34656 |
| Euler totient φ(n) | 17324 |
| Square | 675428121 |
| Cube | 17553701436669 |
| Square root | 161.211042 |
| Digit sum / digital root | 33 / 6 |
| Collatz steps to 1 | 126 |
| Scientific notation | 2.5989 × |
25989 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand nine hundred and eighty-nine |
| Binary (base 2) | 110010110000101 |
| Octal (base 8) | 62605 |
| Hexadecimal (base 16) | 6585 |
| Base 3 | 1022122120 |
| As time | 25989 seconds = 7 h 13 min 9 s |
Is 25989 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 | Yes (25989 ÷ 3 = 8663) | 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 3) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 25989 a prime number?
No. 25989 = 3 × 8663, so it is divisible by 3.
What are the factors of 25989?
1, 3, 8663, 25989.
What is 25989 in binary?
110010110000101 (hexadecimal 6585, octal 62605).
What is the square root of 25989?
About 161.2110.
Is 25989 divisible by 3?
Yes. Its digits add up to 33, a multiple of 3.
What is special about the number 25989?
25989 is a semiprime: 3 × 8663, the product of two primes.