I have been checking it when someone buys a new item. It has said 2,147,483,647 for a very long time and doesn't change. It might be a glitch.

wikipedia link The counter won't go any higher. Make a new shop or get it out!

lol thanks

No problem. xD

Just noting that since this isn't the first time this has been reported, the information was added into the shop sticky:

[topic not found] :)