Prime Numbers Cipher

The encryption uses a correspondence between prime numbers and letters. By default, replace the 26 letters of the alphabet with the 26 first prime numbers (A=2, B=3, C=5, D=7, ..., Z=101).

Example: DCODE is crypted 7,5,47,7,11

Decryption requires knowing the correspondence used between prime numbers and letters. By default, A = 2, B = 3, C = 5, ...

Example: The cipher message is 7,5,47,7,11 then it will be decrypted into DCODE.

The message is only made of prime numbers. The first 26 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 and 101.

It is possible to define an alternative correspondence (or random) between prime numbers and letters.

Example: Random substitution: A=17, B=43, C=101, D=3, etc.

To decode this alternative, convert the numbers into letters using the decryption form and then perform a monoalphabetical substitution.

The South African Scouts Cipher uses prime numbers that are multiplied together. A prime decomposition is necessary.

Example: 110 = 2*5*11 = A,C,E.

In this case, the order of letters is not necessarily preserved (ACE = 2*5*11 = 110 and ECA = 11*5*2 = 110 too), an anagram generator or a permutations generator is useful to find back the right permutation of letters.