difficulty * 2^32 / hash rate / 60 / 60 / 24
(2^256 / (((2^224 - 2^208) / Difficulty) * Hashrate)) / 60 / 60 / 24
WBF1, I try not to express mining chances in lottery terms (although I certainly have in the past). With a lottery, you have a very specific set of numbers in play, which define a closed system that allows you to provide accurate chances at a jackpot win. For example, to guarantee a jackpot win in the powerball, you'd have to purchase 175,223,510 tickets. To guarantee that you just win *something* you need purchase only 35 tickets.
You can't make that same analysis with BTC. Yes, you expect that if you produce 49,692,386,354 shares you will solve a block. However, that's not guaranteed. It might take 1 share, or it might take 100,000,000,000 shares or theoretically that miner may never ever produce a valid block solve.
Because each share is wholly independent and has a chance at solving a block, we can't truly state that "miner X has Y chance" like we can in lottery terms. Furthermore, most every lottery has some kind of prize tiering. Using the powerball again, as long as I match the powerball number, I will win $4. That's why it only takes 35 tickets to guarantee a win. There's no such concept in BTC. You either solve a block or you don't.