Technically, it would be a huge challenge (with some risks)

Firstly, change the code (server and all clients) to handle a much larger number (assuming it's passed around as a 32 bit integer, then the max is 2.14 billion), going beyond that means using a 64 bit integer.

Then the underlying database has to be taken offline, a new 64 bit variable created there, all the data migrated (which, depending on the database software, could mean a total dump and reload).

Then when that's been completed, change the code to load and store it from the server software, pass it to the client from that now 64 bit server variable and finally spin everything back up again.

So you're talking about every character and every retainer on every server needing data migrated from one variable(or column in RDBMS terms) to another one, with the risk that a coding slip-up or 'hiccup' would result in overflow setting a sign bit somewhere and turning someone's gill into a negative few billion.