The number 42765
42765 is a composite number with 8 divisors. Its prime factorisation is 3 × 5 × 2851. Divisors (8): 1, 3, 5, 15, 2851, 8553, 14255, 42765.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42765: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42765 is composite. Its prime factorisation is
- 3
The divisors add up to 68448; without 42765 itself that is 25683, so 42765 is deficient (25683 is less than 42765). Euler's totient φ(42765) = 22800 numbers up to 42765 share no factor with it.
- 4
The digits of 42765 add up to 24, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 163 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42765 = 3 \times 5 \times 2851 \]
42765 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 68448 |
| Euler totient φ(n) | 22800 |
| Square | 1828845225 |
| Cube | 78210566047125 |
| Square root | 206.797002 |
| Digit sum / digital root | 24 / 6 |
| Collatz steps to 1 | 163 |
| Scientific notation | 4.2765 × |
42765 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand seven hundred and sixty-five |
| Binary (base 2) | 1010011100001101 |
| Octal (base 8) | 123415 |
| Hexadecimal (base 16) | A70D |
| Base 3 | 2011122220 |
| As time | 42765 seconds = 11 h 52 min 45 s |
Is 42765 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 (42765 ÷ 3 = 14255) | 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 (42765 ÷ 5 = 8553) | 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 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 5) | 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 42765 a prime number?
No. 42765 = 3 × 5 × 2851, so it is divisible by 3.
What are the factors of 42765?
1, 3, 5, 15, 2851, 8553, 14255, 42765.
What is 42765 in binary?
1010011100001101 (hexadecimal A70D, octal 123415).
What is the square root of 42765?
About 206.7970.
Is 42765 divisible by 3?
Yes. Its digits add up to 24, a multiple of 3.
What is special about the number 42765?
42765 is a happy number: repeatedly adding the squares of its digits reaches 1.