The number 25209
25209 is a composite number with 6 divisors. Its prime factorisation is × 2801. Divisors (6): 1, 3, 9, 2801, 8403, 25209.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
25209 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
25209 is composite. Its prime factorisation is
- 3
The divisors add up to 36426; without 25209 itself that is 11217, so 25209 is deficient (11217 is less than 25209). Euler's totient φ(25209) = 16800 numbers up to 25209 share no factor with it.
- 4
The digits of 25209 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 64 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25209 = 3^{2} \times 2801 \]25209 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 36426 |
| Euler totient φ(n) | 16800 |
| Square | 635493681 |
| Cube | 16020160204329 |
| Square root | 158.773423 (= 3√2801) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 64 |
| Scientific notation | 2.5209 × |
25209 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand two hundred and nine |
| Binary (base 2) | 110001001111001 |
| Octal (base 8) | 61171 |
| Hexadecimal (base 16) | 6279 |
| Base 3 | 1021120200 |
| As time | 25209 seconds = 7 h 0 min 9 s |
Is 25209 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 (25209 ÷ 3 = 8403) | 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 2) | 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 | Yes (25209 ÷ 9 = 2801) | 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 8) | 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 25209 a prime number?
No. 25209 = × 2801, so it is divisible by 3.
What are the factors of 25209?
1, 3, 9, 2801, 8403, 25209.
What is 25209 in binary?
110001001111001 (hexadecimal 6279, octal 61171).
What is the square root of 25209?
About 158.7734, exactly 3√2801.
Is 25209 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 25209?
It is a composite number with 6 divisors.