XnView Software

I have a lot of photos (about 2000) from my last trip. I renamed them (i.e., overwrote the camera numbers with a more descriptive title - hell of a lot of work), then batch numbered them (while retaining the descriptive text) using IrfanView.

Now, after selective culling of the photos to a reasonable number for showing (about 650 photos), I would like to re-number them again (to eliminate gaps in the numbers), without losing the text description. I find that I can no longer do this using IrfanView, because it considers the original numbers along with the descriptive text as part of the title, and simply appends new numbers to the front end. What I want is to replace ONLY the numbers, while retaining the text.

I have not yet installed XnView on my computer. Will XnView do what I want? If so, then I'll install and use it.

Thank you.

and keep the name in filename?

Yes.
As an example, if I have files named
009 Text abc.jpg
016 Text def.jpg
032 Text ghi.jpg
I want to be able to batch renumber them so that the new titles would be
001 Text abc.jpg
002 Text def.jpg
003 Text ghi.jpg
In other words, just change the number part of the filename, but leave the text part as it was.

sorry but not possible