The number 11311
11311 is a palindromic prime: it reads the same backwards and is prime, the 1367th prime number and a palindrome: it reads 11311 backwards too. Its only divisors are 1 and 11311.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 11311: a palindromic prime: it reads the same backwards and is prime; the 1367th prime number; a palindrome: it reads 11311 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
11311 is prime, so its only factors are 1 and 11311. It is the 1367th prime; the next prime is 11317 and the one before is 11299.
- 3
The divisors add up to 11312; without 11311 itself that is 1, so 11311 is deficient (1 is less than 11311). Euler's totient φ(11311) = 11310 numbers up to 11311 share no factor with it.
- 4
The digits of 11311 add up to 7, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 86 steps to reach 1.
11311 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 11312 |
| Euler totient φ(n) | 11310 |
| Square | 127938721 |
| Cube | 1447114873231 |
| Square root | 106.353185 |
| Digit sum / digital root | 7 / 7 |
| Collatz steps to 1 | 86 |
| Scientific notation | 1.1311 × |
11311 in other forms
| Form | Value |
|---|---|
| In words | eleven thousand three hundred and eleven |
| Binary (base 2) | 10110000101111 |
| Octal (base 8) | 26057 |
| Hexadecimal (base 16) | 2C2F |
| Base 3 | 120111221 |
| As time | 11311 seconds = 3 h 8 min 31 s |
Is 11311 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 3) | 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 6) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 11311 a prime number?
Yes. 11311 is divisible only by 1 and itself.
What are the factors of 11311?
1, 11311.
What is 11311 in binary?
10110000101111 (hexadecimal 2C2F, octal 26057).
What is the square root of 11311?
About 106.3532.
Is 11311 divisible by 3?
No. Its digits add up to 7, which is not a multiple of 3.
What is special about the number 11311?
11311 is a palindromic prime: it reads the same backwards and is prime; the 1367th prime number; a palindrome: it reads 11311 backwards too; a happy number: repeatedly adding the squares of its digits reaches 1.