Another utility worth looking into is exiftool. It might not be the right tool in your specific case as it doesn't report any information on the geometry of the document but in general it is probably the most feature-complete tool for inspecting PDF metadata.
Here's an example of a command that will print all available meta information (
-a), sorted by groups (
exiftool -a -G1 "$File"
The official documentation offers an overview of the supported PDF-related tags:
You can install exiftool on Debian/Ubuntu with:
sudo apt-get install libimage-exiftool-perl
If you are more into the GUI side of things you could give my project PDFMtEd a try. It's a set of tools that serve as graphical frontends to exiftool and allow viewing and editing PDF metadata.
Here are a couple of screenshots: