The number 42031
42031 is a composite number with 4 divisors. Its prime factorisation is 11 × 3821. Divisors (4): 1, 11, 3821, 42031.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42031: a semiprime: 11 × 3821, the product of two primes.
- 2
42031 is composite. Its prime factorisation is
- 3
The divisors add up to 45864; without 42031 itself that is 3833, so 42031 is deficient (3833 is less than 42031). Euler's totient φ(42031) = 38200 numbers up to 42031 share no factor with it.
- 4
The digits of 42031 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 106 steps to reach 1.
LaTeX source of the formulas on this page
\[ 42031 = 11 \times 3821 \]
42031 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 45864 |
| Euler totient φ(n) | 38200 |
| Square | 1766604961 |
| Cube | 74252173115791 |
| Square root | 205.014634 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 106 |
| Scientific notation | 4.2031 × |
42031 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and thirty-one |
| Binary (base 2) | 1010010000101111 |
| Octal (base 8) | 122057 |
| Hexadecimal (base 16) | A42F |
| Base 3 | 2010122201 |
| As time | 42031 seconds = 11 h 40 min 31 s |
Is 42031 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 | No (remainder 1) | 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 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | 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 1) | 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 | Yes (42031 ÷ 11 = 3821) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42031 a prime number?
No. 42031 = 11 × 3821, so it is divisible by 11.
What are the factors of 42031?
1, 11, 3821, 42031.
What is 42031 in binary?
1010010000101111 (hexadecimal A42F, octal 122057).
What is the square root of 42031?
About 205.0146.
Is 42031 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 42031?
42031 is a semiprime: 11 × 3821, the product of two primes.