The number 21107
21107 is the 2373rd prime number. Its only divisors are 1 and 21107.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 21107: the 2373rd prime number.
- 2
21107 is prime, so its only factors are 1 and 21107. It is the 2373rd prime; the next prime is 21121 and the one before is 21101.
- 3
The divisors add up to 21108; without 21107 itself that is 1, so 21107 is deficient (1 is less than 21107). Euler's totient φ(21107) = 21106 numbers up to 21107 share no factor with it.
- 4
The digits of 21107 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 105 steps to reach 1.
21107 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 21108 |
| Euler totient φ(n) | 21106 |
| Square | 445505449 |
| Cube | 9403283512043 |
| Square root | 145.282483 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 105 |
| Scientific notation | 2.1107 × |
21107 in other forms
| Form | Value |
|---|---|
| In words | twenty-one thousand one hundred and seven |
| Binary (base 2) | 101001001110011 |
| Octal (base 8) | 51163 |
| Hexadecimal (base 16) | 5273 |
| Base 3 | 1001221202 |
| As time | 21107 seconds = 5 h 51 min 47 s |
Is 21107 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 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | 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 2) | 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 3) | 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 7) | 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 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 21107 a prime number?
Yes. 21107 is divisible only by 1 and itself.
What are the factors of 21107?
1, 21107.
What is 21107 in binary?
101001001110011 (hexadecimal 5273, octal 51163).
What is the square root of 21107?
About 145.2825.
Is 21107 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 21107?
21107 is the 2373rd prime number.