Im tring to do an XOR on 2 hex numbers to create a unique hex number

ex. 7F4 ^ 65D which would equal 1A9

I understand how the XOR should work but every time I try to convert the string hex number:

```
string hex1 = "7F4";
int hexInt = Convert.ToInt32(hex1, 16);
```

I end up with a number: 2036

How do I keep the integrity of the hex number so I can do an XOR on the 2 hex numbers?