Calibre has great support for search and replace using "Regular Expressions". This is what you use to populate series and series no from the authors field, and to clean up the authors field.
Before you start, make sure that you have a good backup of all books, and that you are comfortable with restoring the backup if needed. There is no undo here. None! You have been warned...
The procedure is done in four steps.
1. Identify and select all books with the same naming structure.
2. Create a RegExp to match the series part of the current authors field. Copy the match into the series field.
3. Create a RegExp to match the series number part of the current authors field. Copy the match into the series no field.
4. Create a RegExp to match the actual authors part of the authors field. Replace the current authors field with the match.
There are several threads here on this and similar topics. Also about RegExp. Here is one example that may help a little.