I couldn't comment on Vishal's answer so I will have to write my own.
- The users limit is 2 million in a single site collection.
- As previously mentioned you can add up to 30,000,000 documents per document library or 30,000,000 items per list.
- Again, as previously answered by Vilash you can also manage 400,000 versions.
It is worth noting though that these are out of the box limits and they can be altered by your SharePoint site admins to reduce load on servers. It may be worth consulting your SharePoint admins on the limits specific to your companies instance of SharePoint.
extra: When using Excel in SharePoint it can sometimes be an option to use a list to house the excel data, however this would not be appropriate in your case as the list view threshold limit is 5,000 items. After 5,000 items the list locks up when loading the data for all users and then begins to cause issues with service disruption. As long as you limit the number of items within your list view to less than 5,000 items, you will not run into any issues. The threshold limit can be increased, but is not recommended.
Hope this helps and apologies I could not just simply comment on Vilash's answer!