Permutable Prime Calculator

Input a number to check if it is a Permutable Prime or enter a start and end range to generate all Permutable Primes within that range.

Permutable Prime Check or Generate

What is a Permutable Prime?

A Permutable Prime, also known as a rearrangeable prime, is a unique type of prime number. It is defined as a prime number that remains a prime no matter how its digits are rearranged. For example: The number 13 is a prime. Rearranging its digits gives 13 and 31, both of which are also prime. Therefore, 13 is a Permutable Prime.

Some common Permutable Primes include: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 113, 131, 199, 311, 337, 373, 733, 919, and 991.

How to Identify a Permutable Prime

To check if a number is a Permutable Prime or generate all Permutable Primes within a range, follow these steps:

  1. Check if the number is a prime: Verify that the given number is a prime number.
  2. Generate all permutations: Compute all possible digit arrangements of the number.
  3. Verify primality for all permutations: Check if every rearrangement of the digits is still a prime number. If all permutations are prime, the number is a Permutable Prime; otherwise, it is not.

Examples

Example 1: Is 113 a Permutable Prime?

Solution:

1. Initial prime check:

Verify that 113 is a prime number.

2. Generate permutations:

The permutations of 113 are: 113, 131, and 311.

3. Check primality of permutations:

All permutations (113, 131, 311) are prime.

Result: 113 is a Permutable Prime.

Example 2: Is 197 a Permutable Prime?

Solution:

1. Initial prime check:

Verify that 197 is a prime number.

2. Generate permutations:

The permutations of 197 are: 197, 179, 971, 917, 719, and 791.

3. Check primality of permutations:

Among these, 917 and 791 are not prime.

Result: 197 is not a Permutable Prime.