The number 42139
42139 is the 4405th prime number. Its only divisors are 1 and 42139.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42139: the 4405th prime number.
- 2
42139 is prime, so its only factors are 1 and 42139. It is the 4405th prime; the next prime is 42157 and the one before is 42131.
- 3
The divisors add up to 42140; without 42139 itself that is 1, so 42139 is deficient (1 is less than 42139). Euler's totient φ(42139) = 42138 numbers up to 42139 share no factor with it.
- 4
The digits of 42139 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 80 steps to reach 1.
42139 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 42140 |
| Euler totient φ(n) | 42138 |
| Square | 1775695321 |
| Cube | 74826025131619 |
| Square root | 205.277860 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 80 |
| Scientific notation | 4.2139 × |
42139 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand one hundred and thirty-nine |
| Binary (base 2) | 1010010010011011 |
| Octal (base 8) | 122233 |
| Hexadecimal (base 16) | A49B |
| Base 3 | 2010210201 |
| As time | 42139 seconds = 11 h 42 min 19 s |
Is 42139 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 4) | 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 6) | 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 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 42139 a prime number?
Yes. 42139 is divisible only by 1 and itself.
What are the factors of 42139?
1, 42139.
What is 42139 in binary?
1010010010011011 (hexadecimal A49B, octal 122233).
What is the square root of 42139?
About 205.2779.
Is 42139 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 42139?
42139 is the 4405th prime number.