Simple Data Masking Algorithm

Question

Is there a simple algorithm where by I can convert a numeric value to alphanumeric and reliably convert it back to the same number?

For example, 12345 converts to 00A3DF and back to 12345.

Answer 1

I assume when you say alphanumeric you mean hexadecimal. This has already been answered:

How to convert numbers between hexadecimal and decimal in C#? C# convert integer to hex and back again