rename title of multiple files

New user. Read the class notes but still confused.

I have 13 files with the title of 1furley,2furley,3furley, 13furley.

I want to rename the titles as 14furley,15furley, 27furley.

How can I do this automatically. I don't want to do this for each individual title.

thanks
furley

What is this? The title or the filename?
If it is the filename - fill the tag fields first, then rename the files.
If it is the title field: Is the number really there or should it be in the field track?

Perhaps it is easier to adapt the track number accordingly and then rename the files ...