How much is paid for by the EU and how much by the Member States / businesses / associations / NGOs?
According to Wiki there are now around 23,000 people working for the Commission (plus 9,000 designated 'experts', but I think those only work small loads?). I'd guess the figure for the total EU would be in the 35,000 to 40,000 range.
But then, there is a large number of Member State officials and representatives from business/civil society who also play some part in the EU.
But how many of them are there?