The number 21313
21313 is the 2392nd prime number. Its only divisors are 1 and 21313.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21313: the 2392nd prime number.
- 2
21313 is prime, so its only factors are 1 and 21313. It is the 2392nd prime; the next prime is 21317 and the one before is 21283.
- 3
The divisors add up to 21314; without 21313 itself that is 1, so 21313 is deficient (1 is less than 21313). Euler's totient φ(21313) = 21312 numbers up to 21313 share no factor with it.
- 4
The digits of 21313 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 56 steps to reach 1.
21313 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 21314 |
| Euler totient φ(n) | 21312 |
| Square | 454243969 |
| Cube | 9681301711297 |
| Square root | 145.989726 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 56 |
| Scientific notation | 2.1313 × |
21313 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand three hundred and thirteen |
| Binary (base 2) | 101001101000001 |
| Octal (base 8) | 51501 |
| Hexadecimal (base 16) | 5341 |
| Base 3 | 1002020101 |
| As time | 21313 seconds = 5 h 55 min 13 s |
Is 21313 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 3) | 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 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 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 3) | 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 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21313 a prime number?
Yes. 21313 is divisible only by 1 and itself.
What are the factors of 21313?
1, 21313.
What is 21313 in binary?
101001101000001 (hexadecimal 5341, octal 51501).
What is the square root of 21313?
About 145.9897.
Is 21313 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 21313?
21313 is the 2392nd prime number.