The number 42807
42807 is a composite number with 8 divisors. Its prime factorisation is 3 × 19 × 751. Divisors (8): 1, 3, 19, 57, 751, 2253, 14269, 42807.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42807: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42807 is composite. Its prime factorisation is
- 3
The divisors add up to 60160; without 42807 itself that is 17353, so 42807 is deficient (17353 is less than 42807). Euler's totient φ(42807) = 27000 numbers up to 42807 share no factor with it.
- 4
The digits of 42807 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 194 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42807 = 3 \times 19 \times 751 \]
42807 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 60160 |
| Euler totient φ(n) | 27000 |
| Square | 1832439249 |
| Cube | 78441226931943 |
| Square root | 206.898526 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 194 |
| Scientific notation | 4.2807 × |
42807 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand eight hundred and seven |
| Binary (base 2) | 1010011100110111 |
| Octal (base 8) | 123467 |
| Hexadecimal (base 16) | A737 |
| Base 3 | 2011201110 |
| As time | 42807 seconds = 11 h 53 min 27 s |
Is 42807 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 (42807 ÷ 3 = 14269) | 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 | No (remainder 2) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 6) | 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 42807 a prime number?
No. 42807 = 3 × 19 × 751, so it is divisible by 3.
What are the factors of 42807?
1, 3, 19, 57, 751, 2253, 14269, 42807.
What is 42807 in binary?
1010011100110111 (hexadecimal A737, octal 123467).
What is the square root of 42807?
About 206.8985.
Is 42807 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 42807?
42807 is a happy number: repeatedly adding the squares of its digits reaches 1.