The number 42831
42831 is a composite number with 6 divisors. Its prime factorisation is × 4759. Divisors (6): 1, 3, 9, 4759, 14277, 42831.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42831: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42831 is composite. Its prime factorisation is
- 3
The divisors add up to 61880; without 42831 itself that is 19049, so 42831 is deficient (19049 is less than 42831). Euler's totient φ(42831) = 28548 numbers up to 42831 share no factor with it.
- 4
The digits of 42831 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 88 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42831 = 3^{2} \times 4759 \]42831 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 61880 |
| Euler totient φ(n) | 28548 |
| Square | 1834494561 |
| Cube | 78573236542191 |
| Square root | 206.956517 (= 3√4759) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 88 |
| Scientific notation | 4.2831 × |
42831 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand eight hundred and thirty-one |
| Binary (base 2) | 1010011101001111 |
| Octal (base 8) | 123517 |
| Hexadecimal (base 16) | A74F |
| Base 3 | 2011202100 |
| As time | 42831 seconds = 11 h 53 min 51 s |
Is 42831 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 (42831 ÷ 3 = 14277) | 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 1) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (42831 ÷ 9 = 4759) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | 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 3) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42831 a prime number?
No. 42831 = × 4759, so it is divisible by 3.
What are the factors of 42831?
1, 3, 9, 4759, 14277, 42831.
What is 42831 in binary?
1010011101001111 (hexadecimal A74F, octal 123517).
What is the square root of 42831?
About 206.9565, exactly 3√4759.
Is 42831 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 42831?
42831 is a happy number: repeatedly adding the squares of its digits reaches 1.