Sure.
- Hold down the Ctrl+Shift keys (on a Windows system) or Cmd+Shift keys (on a Mac) and double-click on the compound page number. This releases the content from the parent page and places the content on your document page. It also changes your Arrow/Selection tool cursor to a Text tool cursor.
- Highlight the first page number in your X of Y compound page numbering and change it to the number you want it to be.
Realize that as you do this, you will break the internal coding that automatically determines the page number in your document. If the page count changes in your document, or in any other document that has combined with this document into an InDesign book file, your edited page number will not change and you will have to manually correct the number again.
It's a bit of a rude cure, but it's one that will work for you — with limitations.
Hope this helps,
Randy