1 Milliiom BTC = $32 Billion usd.
There's not one address holding a million Bitcoin, you'll need to brute-force 20,000 different addresses. There are
currently 5,739 addresses holding exactly 50 Bitcoin, and 37,003 addresses holding 50.x Bitcoin (I can imagine many of those addresses have received some dust over the years).
if there is 1 Million Brute-Force miners = $1 BTC each.
You can try as long as you want, you'll never find a randomly generated private key. This image comes to mind:
I would refer you to the below picture to help you understand the probability of finding a "random" private key with coin in it:
There are 2^160 possible private keys. For comparison, there are currently approximately 2^26 unspent outputs, however some addresses have multiple unspent outputs.
If a private key was generated
randomly, for all intents and purposes, it is not going to be found out via a
brute force attack.