The number 6221
6221 is the 810th prime number. Its only divisors are 1 and 6221.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 6221: the 810th prime number.
- 2
6221 is prime, so its only factors are 1 and 6221. It is the 810th prime; the next prime is 6229 and the one before is 6217.
- 3
The divisors add up to 6222; without 6221 itself that is 1, so 6221 is deficient (1 is less than 6221). Euler's totient φ(6221) = 6220 numbers up to 6221 share no factor with it.
- 4
The digits of 6221 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 36 steps to reach 1.
6221 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 6222 |
| Euler totient φ(n) | 6220 |
| Square | 38700841 |
| Cube | 240757931861 |
| Square root | 78.873316 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 36 |
| Scientific notation | 6.221 × |
6221 in other forms
| Form | Value |
|---|---|
| In words | six thousand two hundred and twenty-one |
| Binary (base 2) | 1100001001101 |
| Octal (base 8) | 14115 |
| Hexadecimal (base 16) | 184D |
| Base 3 | 22112102 |
| As time | 6221 seconds = 1 h 43 min 41 s |
Is 6221 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 5) | 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 2) | 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 6) | 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 6221 a prime number?
Yes. 6221 is divisible only by 1 and itself.
What are the factors of 6221?
1, 6221.
What is 6221 in binary?
1100001001101 (hexadecimal 184D, octal 14115).
What is the square root of 6221?
About 78.8733.
Is 6221 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 6221?
6221 is the 810th prime number.