The number 42071
42071 is a twin prime (42071 and 42073 are both prime) and the 4399th prime number. Its only divisors are 1 and 42071.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 42071: a twin prime (42071 and 42073 are both prime); the 4399th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
42071 is prime, so its only factors are 1 and 42071. It is the 4399th prime; the next prime is 42073 and the one before is 42061.
- 3
The divisors add up to 42072; without 42071 itself that is 1, so 42071 is deficient (1 is less than 42071). Euler's totient φ(42071) = 42070 numbers up to 42071 share no factor with it.
- 4
The digits of 42071 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 31 steps to reach 1.
42071 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 42072 |
| Euler totient φ(n) | 42070 |
| Square | 1769969041 |
| Cube | 74464367523911 |
| Square root | 205.112164 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 31 |
| Scientific notation | 4.2071 × |
42071 in other forms
| Form | Value |
|---|---|
| In words | forty-two thousand and seventy-one |
| Binary (base 2) | 1010010001010111 |
| Octal (base 8) | 122127 |
| Hexadecimal (base 16) | A457 |
| Base 3 | 2010201012 |
| As time | 42071 seconds = 11 h 41 min 11 s |
Is 42071 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 1) | 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 5) | 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 7) | 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 42071 a prime number?
Yes. 42071 is divisible only by 1 and itself.
What are the factors of 42071?
1, 42071.
What is 42071 in binary?
1010010001010111 (hexadecimal A457, octal 122127).
What is the square root of 42071?
About 205.1122.
Is 42071 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 42071?
42071 is a twin prime (42071 and 42073 are both prime); the 4399th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.