The number 82009
82009 is a twin prime (82007 and 82009 are both prime) and the 8020th prime number. Its only divisors are 1 and 82009.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 82009: a twin prime (82007 and 82009 are both prime); the 8020th prime number.
- 2
82009 is prime, so its only factors are 1 and 82009. It is the 8020th prime; the next prime is 82013 and the one before is 82007.
- 3
The divisors add up to 82010; without 82009 itself that is 1, so 82009 is deficient (1 is less than 82009). Euler's totient φ(82009) = 82008 numbers up to 82009 share no factor with it.
- 4
The digits of 82009 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 63 steps to reach 1.
82009 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 82010 |
| Euler totient φ(n) | 82008 |
| Square | 6725476081 |
| Cube | 551549567926729 |
| Square root | 286.372136 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 63 |
| Scientific notation | 8.2009 × |
82009 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand and nine |
| Binary (base 2) | 10100000001011001 |
| Octal (base 8) | 240131 |
| Hexadecimal (base 16) | 14059 |
| Base 3 | 11011111101 |
| As time | 82009 seconds = 22 h 46 min 49 s |
Is 82009 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 1) | 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 4) | 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 82009 a prime number?
Yes. 82009 is divisible only by 1 and itself.
What are the factors of 82009?
1, 82009.
What is 82009 in binary?
10100000001011001 (hexadecimal 14059, octal 240131).
What is the square root of 82009?
About 286.3721.
Is 82009 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 82009?
82009 is a twin prime (82007 and 82009 are both prime); the 8020th prime number.