You must use a seperator for the two numbers. Then, use str_stri to get the position of the seperator and a combination of str_clip and str_trunc to "extract" the two values...
You don't always need a seperator if you know the length of the integer you're sending
If you're always sending the same length integer, just use str_clip() and str_trunc() to and extract the length you need
If you're changing the length of the integer, just concatenate that into the string
