The number 57221
57221 is a twin prime (57221 and 57223 are both prime) and the 5803rd prime number. Its only divisors are 1 and 57221.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 57221: a twin prime (57221 and 57223 are both prime); the 5803rd prime number.
- 2
57221 is prime, so its only factors are 1 and 57221. It is the 5803rd prime; the next prime is 57223 and the one before is 57203.
- 3
The divisors add up to 57222; without 57221 itself that is 1, so 57221 is deficient (1 is less than 57221). Euler's totient φ(57221) = 57220 numbers up to 57221 share no factor with it.
- 4
The digits of 57221 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 52 steps to reach 1.
57221 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 57222 |
| Euler totient φ(n) | 57220 |
| Square | 3274242841 |
| Cube | 187355449604861 |
| Square root | 239.209114 |
| Digit sum / digital root | 17 / 8 |
| Collatz steps to 1 | 52 |
| Scientific notation | 5.7221 × |
57221 in other forms
| Form | Value |
|---|---|
| In words | fifty-seven thousand two hundred and twenty-one |
| Binary (base 2) | 1101111110000101 |
| Octal (base 8) | 157605 |
| Hexadecimal (base 16) | DF85 |
| Base 3 | 2220111022 |
| As time | 57221 seconds = 15 h 53 min 41 s |
Is 57221 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 10) | 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 57221 a prime number?
Yes. 57221 is divisible only by 1 and itself.
What are the factors of 57221?
1, 57221.
What is 57221 in binary?
1101111110000101 (hexadecimal DF85, octal 157605).
What is the square root of 57221?
About 239.2091.
Is 57221 divisible by 3?
No. Its digits add up to 17, which is not a multiple of 3.
What is special about the number 57221?
57221 is a twin prime (57221 and 57223 are both prime); the 5803rd prime number.