The number 18225
18225 is a perfect square (135²). Its prime factorisation is × . Divisors (21): 1, 3, 5, 9, 15, 25, 27, 45, 75, 81, 135, 225, 243, 405, 675, 729 … 18225.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18225: a perfect square (135²).
- 2
18225 is composite. Its prime factorisation is
- 3
The divisors add up to 33883; without 18225 itself that is 15658, so 18225 is deficient (15658 is less than 18225). Euler's totient φ(18225) = 9720 numbers up to 18225 share no factor with it.
- 4
The digits of 18225 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 61 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18225 = 3^{6} \times 5^{2} \]18225 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 21 |
| Sum of divisors | 33883 |
| Euler totient φ(n) | 9720 |
| Square | 332150625 |
| Cube | 6053445140625 |
| Square root | 135 |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 61 |
| Scientific notation | 1.8225 × |
| Perfect power |
18225 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand two hundred and twenty-five |
| Binary (base 2) | 100011100110001 |
| Octal (base 8) | 43461 |
| Hexadecimal (base 16) | 4731 |
| Base 3 | 221000000 |
| As time | 18225 seconds = 5 h 3 min 45 s |
Is 18225 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 (18225 ÷ 3 = 6075) | 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 | Yes (18225 ÷ 5 = 3645) | 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 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 | Yes (18225 ÷ 9 = 2025) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | 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 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18225 a prime number?
No. 18225 = × , so it is divisible by 3.
What are the factors of 18225?
1, 3, 5, 9, 15, 25, 27, 45, 75, 81, 135, 225, 243, 405, 675, 729, 1215, 2025, 3645, 6075, 18225.
What is 18225 in binary?
100011100110001 (hexadecimal 4731, octal 43461).
What is the square root of 18225?
135, because 135 × 135 = 18225.
Is 18225 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 18225?
18225 is a perfect square (135²).