If you have 100 or more slides in your presentation and go to Articulate > Audio Editor > Import > Multiple Files, you will find that slide numbers beyond 99 do not display correctly. Only the first two digits will display. For example, slide 110 will show as 11. (However, when you are asked to "Confirm narration import order", the full slide numbers will display as expected.)
This is a known issue. If you need to see the full slide numbers, you can use the Import Audio feature rather than the Audio Editor to import audio files.