Just completed this game on notdoppler without hacking/cheating, moving the clock forward etc. Millionaire To Billionaire is similar to the original Adventure Capitalist.

Screenshots

Took about a week and found the game's weaknesses soon enough.

Spoiler follows:
.
.
.
At around 30 million Prestige the trick is to not to reset the Prestige at all any more because that wastes time but just rely on the free periodic upgrades the game gives you every few minutes. Work on trying to earn the most money to get the upgrades cleared one by one.

At some point the income earned by the commodities will be completely swamped by the automatic rewards the game gives you. The game usually offers you a choice between a free investment or the money equivalent and most of the time it's best to take the money so you can spend it in the most efficient way.

As you can see in the screenshots the game ends when the upgrades run out and each commodity costs an infinite amount of money so you can't build the investments any further. Nothing special happens at this point, the rewards still come in periodically but the money isn't significant enough to increase the total, game over.