Help with a regular expression

I need to make a regular expression that will help me format a number in this way.

Example: We have this number222345678

I need an expression that can do this:22 234 5678

That is, after the first 2 numbers add a space, then add one after the next 3 and the last block is 4 numbers.

I currently have something like this:number.toString().replace(/\d{4,4}?(?=...)/g, "$& ")

Which only separates them every 4.

I have searched for an expression that does the same thing but I can't find anything, does anyone know how to do it? Beforehand thank you very much.