The number 42075
42075 is a composite number with 36 divisors. Its prime factorisation is × × 11 × 17. Divisors (36): 1, 3, 5, 9, 11, 15, 17, 25, 33, 45, 51, 55, 75, 85, 99, 153 … 42075.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42075: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42075 is composite. Its prime factorisation is
- 3
The divisors add up to 87048; without 42075 itself that is 44973, so 42075 is abundant (44973 is more than 42075). Euler's totient φ(42075) = 19200 numbers up to 42075 share no factor with it.
- 4
The digits of 42075 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 150 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42075 = 3^{2} \times 5^{2} \times 11 \times 17 \]42075 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 36 |
| Sum of divisors | 87048 |
| Euler totient φ(n) | 19200 |
| Square | 1770305625 |
| Cube | 74485609171875 |
| Square root | 205.121915 (= 15√187) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 150 |
| Scientific notation | 4.2075 × |
42075 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and seventy-five |
| Binary (base 2) | 1010010001011011 |
| Octal (base 8) | 122133 |
| Hexadecimal (base 16) | A45B |
| Base 3 | 2010201100 |
| As time | 42075 seconds = 11 h 41 min 15 s |
Is 42075 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 (42075 ÷ 3 = 14025) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (42075 ÷ 5 = 8415) | 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 5) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (42075 ÷ 9 = 4675) | 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 | Yes (42075 ÷ 11 = 3825) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42075 a prime number?
No. 42075 = × × 11 × 17, so it is divisible by 3.
What are the factors of 42075?
1, 3, 5, 9, 11, 15, 17, 25, 33, 45, 51, 55, 75, 85, 99, 153, 165, 187, 225, 255, 275, 425, 495, 561, 765, 825, 935, 1275, 1683, 2475, 2805, 3825, 4675, 8415, 14025, 42075.
What is 42075 in binary?
1010010001011011 (hexadecimal A45B, octal 122133).
What is the square root of 42075?
About 205.1219, exactly 15√187.
Is 42075 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 42075?
42075 is a happy number: repeatedly adding the squares of its digits reaches 1.