The number 31321
31321 is a twin prime (31319 and 31321 are both prime) and the 3376th prime number. Its only divisors are 1 and 31321.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 31321: a twin prime (31319 and 31321 are both prime); the 3376th prime number.
- 2
31321 is prime, so its only factors are 1 and 31321. It is the 3376th prime; the next prime is 31327 and the one before is 31319.
- 3
The divisors add up to 31322; without 31321 itself that is 1, so 31321 is deficient (1 is less than 31321). Euler's totient φ(31321) = 31320 numbers up to 31321 share no factor with it.
- 4
The digits of 31321 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 85 steps to reach 1.
31321 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 31322 |
| Euler totient φ(n) | 31320 |
| Square | 981005041 |
| Cube | 30726058889161 |
| Square root | 176.977400 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 85 |
| Scientific notation | 3.1321 × |
31321 in other forms
| Form | Value |
|---|---|
| In words | thirty-one thousand three hundred and twenty-one |
| Binary (base 2) | 111101001011001 |
| Octal (base 8) | 75131 |
| Hexadecimal (base 16) | 7A59 |
| Base 3 | 1120222001 |
| As time | 31321 seconds = 8 h 42 min 1 s |
Is 31321 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 1) | 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 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 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 1) | 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 31321 a prime number?
Yes. 31321 is divisible only by 1 and itself.
What are the factors of 31321?
1, 31321.
What is 31321 in binary?
111101001011001 (hexadecimal 7A59, octal 75131).
What is the square root of 31321?
About 176.9774.
Is 31321 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 31321?
31321 is a twin prime (31319 and 31321 are both prime); the 3376th prime number.