The number 71387
71387 is a twin prime (71387 and 71389 are both prime) and the 7069th prime number. Its only divisors are 1 and 71387.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 71387: a twin prime (71387 and 71389 are both prime); the 7069th prime number.
- 2
71387 is prime, so its only factors are 1 and 71387. It is the 7069th prime; the next prime is 71389 and the one before is 71363.
- 3
The divisors add up to 71388; without 71387 itself that is 1, so 71387 is deficient (1 is less than 71387). Euler's totient φ(71387) = 71386 numbers up to 71387 share no factor with it.
- 4
The digits of 71387 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 125 steps to reach 1.
71387 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 71388 |
| Euler totient φ(n) | 71386 |
| Square | 5096103769 |
| Cube | 363795559757603 |
| Square root | 267.183458 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 125 |
| Scientific notation | 7.1387 × |
71387 in other forms
| Form | Value |
|---|---|
| In words | seventy-one thousand three hundred and eighty-seven |
| Binary (base 2) | 10001011011011011 |
| Octal (base 8) | 213333 |
| Hexadecimal (base 16) | 116DB |
| Base 3 | 10121220222 |
| As time | 71387 seconds = 19 h 49 min 47 s |
Is 71387 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 2) | 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 3) | 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 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | 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 71387 a prime number?
Yes. 71387 is divisible only by 1 and itself.
What are the factors of 71387?
1, 71387.
What is 71387 in binary?
10001011011011011 (hexadecimal 116DB, octal 213333).
What is the square root of 71387?
About 267.1835.
Is 71387 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 71387?
71387 is a twin prime (71387 and 71389 are both prime); the 7069th prime number.