The number 30825
30825 is a composite number with 18 divisors. Its prime factorisation is × × 137. Divisors (18): 1, 3, 5, 9, 15, 25, 45, 75, 137, 225, 411, 685, 1233, 2055, 3425, 6165 … 30825.
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How to work it out
- 1
30825 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
30825 is composite. Its prime factorisation is
- 3
The divisors add up to 55614; without 30825 itself that is 24789, so 30825 is deficient (24789 is less than 30825). Euler's totient φ(30825) = 16320 numbers up to 30825 share no factor with it.
- 4
The digits of 30825 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 134 steps to reach 1.
LaTeX source of the formulas on this page
\[ 30825 = 3^{2} \times 5^{2} \times 137 \]30825 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 55614 |
| Euler totient φ(n) | 16320 |
| Square | 950180625 |
| Cube | 29289317765625 |
| Square root | 175.570499 (= 15√137) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 134 |
| Scientific notation | 3.0825 × |
30825 in other forms
| Form | Value |
|---|---|
| In words | thirty thousand eight hundred and twenty-five |
| Binary (base 2) | 111100001101001 |
| Octal (base 8) | 74151 |
| Hexadecimal (base 16) | 7869 |
| Base 3 | 1120021200 |
| As time | 30825 seconds = 8 h 33 min 45 s |
Is 30825 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 (30825 ÷ 3 = 10275) | 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 (30825 ÷ 5 = 6165) | 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 (30825 ÷ 9 = 3425) | 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 3) | 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 30825 a prime number?
No. 30825 = × × 137, so it is divisible by 3.
What are the factors of 30825?
1, 3, 5, 9, 15, 25, 45, 75, 137, 225, 411, 685, 1233, 2055, 3425, 6165, 10275, 30825.
What is 30825 in binary?
111100001101001 (hexadecimal 7869, octal 74151).
What is the square root of 30825?
About 175.5705, exactly 15√137.
Is 30825 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 30825?
It is a composite number with 18 divisors.