There's no command to select specifically 40K files.

But you can click the first file, then scroll the panel by dragging the scroll bar to little over half of the list (40/75) and click on some file there, while holding down Shift key. That will select all files between the first and the selected file. It won't be 40K exactly, but you can get pretty near. You can fine-tune the selection to get near (or exactly at) 40K by keeping Shift-clicking on other "last" files.

Hello!

I'm trying to select and download multiple image files ,jpg within a large directory that's about 1,630 MB, which totals about 75,000 images. I only want to select 40,000 images out of the 75,000. Please advice as what would be the command to use to select all 40,000 with one strike.

Thanks You
Bill B