A semantically secure public-key cryptosystem based on RSA

We present a semantically secure public-key cryptosystem based on the RSA cryptosystem. We describe possible preferences of the proposed cryptosystem with respect to the basic RSA cryptosystem. These preferences include a semantic security property, as well as more various choice of an encryption key, and the possibility to select this key by an ordinary user. It is shown that the knowledge of the modulus factorization does not allow to break the cryptosystem as it happens in the basic RSA.