The number 82421
82421 is the 8057th prime number. Its only divisors are 1 and 82421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 82421: the 8057th prime number.
- 2
82421 is prime, so its only factors are 1 and 82421. It is the 8057th prime; the next prime is 82457 and the one before is 82393.
- 3
The divisors add up to 82422; without 82421 itself that is 1, so 82421 is deficient (1 is less than 82421). Euler's totient φ(82421) = 82420 numbers up to 82421 share no factor with it.
- 4
The digits of 82421 add up to 17, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 94 steps to reach 1.
82421 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 82422 |
| Euler totient φ(n) | 82420 |
| Square | 6793221241 |
| Cube | 559904087904461 |
| Square root | 287.090578 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 94 |
| Scientific notation | 8.2421 × |
82421 in other forms
| Form | Value |
|---|---|
| In words | eighty-two thousand four hundred and twenty-one |
| Binary (base 2) | 10100000111110101 |
| Octal (base 8) | 240765 |
| Hexadecimal (base 16) | 141F5 |
| Base 3 | 11012001122 |
| As time | 82421 seconds = 22 h 53 min 41 s |
Is 82421 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 3) | 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 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 9) | 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 82421 a prime number?
Yes. 82421 is divisible only by 1 and itself.
What are the factors of 82421?
1, 82421.
What is 82421 in binary?
10100000111110101 (hexadecimal 141F5, octal 240765).
What is the square root of 82421?
About 287.0906.
Is 82421 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 82421?
82421 is the 8057th prime number.