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 53,61,23,41,11 will be decrypted into PRIME

The message is only made of prime numbers, mainly the first 26 prime numbers: $ 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, 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 prime multiplicaiton cipher (rarely called 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.