It's encrypted text. It's just a stream of bytes.
If you want to send it as text, use base64
or something similar.
And one more thing. It is not directly related to your question, but it is very important. You are using RSA in a very wrong way. Your code is totally insecure.
The right thing to do is generate a fixed-length random key and use it for symmetric encryption (I'd suggest AES in CTR mode) of your data. Then you should use PKCS#1-OAEP at the beginning of your session only to establish this key.