You can add multiple sorting on the same field.
You can apply different sort as below.
1. Ascending/Descending by Data source/ Alphabetical order.
2. Using a field from data source.
3. Manual on sheet by drag the field and drop where required.
Select the field and sort using number as ascending order using ascending sort button below format tab. Now click on field for 2nd sort and choose field and select category to sort by category order.
Now your data is sorted by number wise and category wise.
Hope this helps you.