I wonder how many people Trump has working for him. He owns the casinos in AC and Vegas, all his properties world wide. He must have a pretty significant amount of employees.
He owns a piece of those casinos. He lost controlling interest a little while ago, during the time the corporation was going through reorganization through bankruptcy. It's now known as Trump Entertainment Resorts. Trump is a minority owner in that company, and is not involved in the management anymore - which was part of the restructuring deal. That company pays Trump a licensing fee to use his name and likeness.
Trump however does continue to own and operate his private real estate development firm which I believe is called "Trump Organization". It has a multitude of real estate and resort assets as well as other non-real estate business interests, like the Miss USA pageant for example.
The last I read, and this was a year or so ago, that organization employed almost 25K people. So, it is a pretty good sized company.