Dear all, Basically I am thinking of a possibility that I could transform several numbers into one using a key, which is reversible by using the same key afterwards, transform the one number back into its original separated form. I am not really good in number theory or cryptography but I tried searching on Google, I see that there might be some solutions in these fields but I am not sure whether this is feasible. I do understand that doing that will cause some errors so I would like to study it. In fact, I am thinking that representing the numbers using ASCII and perform some mathematical transformation might produce far better results than pure number manipulation. Does anyone have any idea or experience of doing this? If yes, is there any reference source that you may provide? Thank you so much! p/s: I am doing this because I just want to compress a large array of data into a small size to save power on wireless radio transmission.