The number 80749
80749 is a twin prime (80747 and 80749 are both prime) and the 7903rd prime number. Its only divisors are 1 and 80749.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 80749: a twin prime (80747 and 80749 are both prime); the 7903rd prime number.
- 2
80749 is prime, so its only factors are 1 and 80749. It is the 7903rd prime; the next prime is 80761 and the one before is 80747.
- 3
The divisors add up to 80750; without 80749 itself that is 1, so 80749 is deficient (1 is less than 80749). Euler's totient φ(80749) = 80748 numbers up to 80749 share no factor with it.
- 4
The digits of 80749 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 169 steps to reach 1.
80749 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 80750 |
| Euler totient φ(n) | 80748 |
| Square | 6520401001 |
| Cube | 526515860429749 |
| Square root | 284.163685 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 169 |
| Scientific notation | 8.0749 × |
80749 in other forms
| Form | Value |
|---|---|
| In words | eighty thousand seven hundred and forty-nine |
| Binary (base 2) | 10011101101101101 |
| Octal (base 8) | 235555 |
| Hexadecimal (base 16) | 13B6D |
| Base 3 | 11002202201 |
| As time | 80749 seconds = 22 h 25 min 49 s |
Is 80749 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 1) | 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 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 5) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 80749 a prime number?
Yes. 80749 is divisible only by 1 and itself.
What are the factors of 80749?
1, 80749.
What is 80749 in binary?
10011101101101101 (hexadecimal 13B6D, octal 235555).
What is the square root of 80749?
About 284.1637.
Is 80749 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 80749?
80749 is a twin prime (80747 and 80749 are both prime); the 7903rd prime number.