The number 67391
67391 is the 6711th prime number. Its only divisors are 1 and 67391.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 67391: the 6711th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
67391 is prime, so its only factors are 1 and 67391. It is the 6711th prime; the next prime is 67399 and the one before is 67369.
- 3
The divisors add up to 67392; without 67391 itself that is 1, so 67391 is deficient (1 is less than 67391). Euler's totient φ(67391) = 67390 numbers up to 67391 share no factor with it.
- 4
The digits of 67391 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 161 steps to reach 1.
67391 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 67392 |
| Euler totient φ(n) | 67390 |
| Square | 4541546881 |
| Cube | 306059385857471 |
| Square root | 259.597766 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 161 |
| Scientific notation | 6.7391 × |
67391 in other forms
| Form | Value |
|---|---|
| In words | sixty-seven thousand three hundred and ninety-one |
| Binary (base 2) | 10000011100111111 |
| Octal (base 8) | 203477 |
| Hexadecimal (base 16) | 1073F |
| Base 3 | 10102102222 |
| As time | 67391 seconds = 18 h 43 min 11 s |
Is 67391 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 2) | 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 8) | 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 5) | 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 67391 a prime number?
Yes. 67391 is divisible only by 1 and itself.
What are the factors of 67391?
1, 67391.
What is 67391 in binary?
10000011100111111 (hexadecimal 1073F, octal 203477).
What is the square root of 67391?
About 259.5978.
Is 67391 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 67391?
67391 is the 6711th prime number; a happy number: repeatedly adding the squares of its digits reaches 1.