RSA Encoding Decoding

Here is an example which illustrates how RSA method works. What you do is start with two prime numbers and multiply them to get a bigger composite number. This number is not easy to factor so you make this number public. Let’s call it . Then you find the number of relative primes of this composite number using Euler phi function and then find a number relative prime to this euler phi number. You make this new number also public. Let’s call this number . The private number comes from using the euclid’s algorithm and is the coefficient of the new number, lets call it . Now any number can be encoded as and to decode it