The number 42131
42131 is the 4404th prime number. Its only divisors are 1 and 42131.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42131: the 4404th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42131 is prime, so its only factors are 1 and 42131. It is the 4404th prime; the next prime is 42139 and the one before is 42101.
- 3
The divisors add up to 42132; without 42131 itself that is 1, so 42131 is deficient (1 is less than 42131). Euler's totient φ(42131) = 42130 numbers up to 42131 share no factor with it.
- 4
The digits of 42131 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 106 steps to reach 1.
42131 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 42132 |
| Euler totient φ(n) | 42130 |
| Square | 1775021161 |
| Cube | 74783416534091 |
| Square root | 205.258374 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 106 |
| Scientific notation | 4.2131 × |
42131 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand one hundred and thirty-one |
| Binary (base 2) | 1010010010010011 |
| Octal (base 8) | 122223 |
| Hexadecimal (base 16) | A493 |
| Base 3 | 2010210102 |
| As time | 42131 seconds = 11 h 42 min 11 s |
Is 42131 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 2) | 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 5) | 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 | No (remainder 2) | 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 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 42131 a prime number?
Yes. 42131 is divisible only by 1 and itself.
What are the factors of 42131?
1, 42131.
What is 42131 in binary?
1010010010010011 (hexadecimal A493, octal 122223).
What is the square root of 42131?
About 205.2584.
Is 42131 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 42131?
42131 is the 4404th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.