The number 40725
40725 is a composite number with 18 divisors. Its prime factorisation is × × 181. Divisors (18): 1, 3, 5, 9, 15, 25, 45, 75, 181, 225, 543, 905, 1629, 2715, 4525, 8145 … 40725.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 40725: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
40725 is composite. Its prime factorisation is
- 3
The divisors add up to 73346; without 40725 itself that is 32621, so 40725 is deficient (32621 is less than 40725). Euler's totient φ(40725) = 21600 numbers up to 40725 share no factor with it.
- 4
The digits of 40725 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 44 steps to reach 1.
LaTeX source of the formulas on this page
\[ 40725 = 3^{2} \times 5^{2} \times 181 \]40725 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 18 |
| Sum of divisors | 73346 |
| Euler totient φ(n) | 21600 |
| Square | 1658525625 |
| Cube | 67543456078125 |
| Square root | 201.804361 (= 15√181) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 44 |
| Scientific notation | 4.0725 × |
40725 in other forms
| Form | Value |
|---|---|
| In words | forty thousand seven hundred and twenty-five |
| Binary (base 2) | 1001111100010101 |
| Octal (base 8) | 117425 |
| Hexadecimal (base 16) | 9F15 |
| Base 3 | 2001212100 |
| As time | 40725 seconds = 11 h 18 min 45 s |
Is 40725 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 (40725 ÷ 3 = 13575) | 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 (40725 ÷ 5 = 8145) | 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 6) | 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 | Yes (40725 ÷ 9 = 4525) | 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 40725 a prime number?
No. 40725 = × × 181, so it is divisible by 3.
What are the factors of 40725?
1, 3, 5, 9, 15, 25, 45, 75, 181, 225, 543, 905, 1629, 2715, 4525, 8145, 13575, 40725.
What is 40725 in binary?
1001111100010101 (hexadecimal 9F15, octal 117425).
What is the square root of 40725?
About 201.8044, exactly 15√181.
Is 40725 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 40725?
40725 is a happy number: repeatedly adding the squares of its digits reaches 1.