I like to work, but I'd quit any full-time job I had. I might work as a regular part-timer at some point, once I'd done whatever else I wanted to do for a while.
I wouldn't keep much (relatively) for myself, though I'd probably buy a slightly larger, newer and nicer condo than the 810-square-foot, 45-year-old one that I own now (and am close to paying off). I'd buy a new car -- probably a Mini Cooper, like I've wanted for a while, or, dare I say it, maybe just another Toyota Corolla (the one I drive now is 15 years old and has 273,000 miles on it, but it still runs fine and has given me no problems, so it's hard to ignore that, though it may be basic and boring, it's really a perfect-sized, functional, and well-functioning car, and I may just get another one).
I'd give at least a few million to my mom and a million or two to each of my siblings, and I'd keep a good chunk to buy/flip a house just because that's something I've always wanted to do. Likewise, I'd take a long cruise -- at least a month, and maybe two -- just to see how I liked it.
Beyond that, though, much of the money would go to missionary work and nature conservation. I'd like to go on a few trips, and/or become involved in some truly meaningful projects in this manner. Otherwise, I'd keep $2 million for my own savings/investing.
The rest would just be given away.
I literally can't imagine having that much money to be able to do so much good, and not doing it. And, generally speaking, I think it's a disgraceful waste that one person, or even a couple/few people, can, and do, regularly win so much money, without any effort required beyond buying a ticket.