OK, sure, but if you want something more to do with ciphertexts than with key generation, consider this: "textbook" RSA is not secure. The reason is that the

OK, sure, but if you want something more to do with ciphertexts than with key generation, consider this: "textbook" RSA is not secure. The reason is that the "textbook" RSA algorithm is not randomized; that is also the reason why so much effort has gone into randomized padding schemes like this: https://en.wikipedia.org/wiki/OAEP https://en.wikipedia.org/wiki/OAEP