The number 77081
77081 is the 7575th prime number. Its only divisors are 1 and 77081.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 77081: the 7575th prime number.
- 2
77081 is prime, so its only factors are 1 and 77081. It is the 7575th prime; the next prime is 77093 and the one before is 77069.
- 3
The divisors add up to 77082; without 77081 itself that is 1, so 77081 is deficient (1 is less than 77081). Euler's totient φ(77081) = 77080 numbers up to 77081 share no factor with it.
- 4
The digits of 77081 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 81 steps to reach 1.
77081 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 77082 |
| Euler totient φ(n) | 77080 |
| Square | 5941480561 |
| Cube | 457975263122441 |
| Square root | 277.634652 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 81 |
| Scientific notation | 7.7081 × |
77081 in other forms
| Form | Value |
|---|---|
| In words | seventy-seven thousand and eighty-one |
| Binary (base 2) | 10010110100011001 |
| Octal (base 8) | 226431 |
| Hexadecimal (base 16) | 12D19 |
| Base 3 | 10220201212 |
| As time | 77081 seconds = 21 h 24 min 41 s |
Is 77081 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 1) | 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 4) | 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 1) | 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 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 77081 a prime number?
Yes. 77081 is divisible only by 1 and itself.
What are the factors of 77081?
1, 77081.
What is 77081 in binary?
10010110100011001 (hexadecimal 12D19, octal 226431).
What is the square root of 77081?
About 277.6347.
Is 77081 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 77081?
77081 is the 7575th prime number.