^^^ With 8 billion people on Earth, that's (on average) 262500 satoshi's per person. Plenty enough to do business with.
If you divide 21 million bitcoin by 8 billion people, there's enough bitcoin for each person to have 262500 satoshi'.
But millioner/ billioner are accounlate 30% of total btc amount so what happen the price if whole of the world aware about btc?
Yes, 21 million bitcoins divided by 8 billion people equals 262,500 satoshis for each person. Here the millionaire billionaires own 30% and the remaining 70 percent is with you and all the small and big investors. Now if the whole world is aware of Bitcoin and ready to invest then the price of Bitcoin will be such that millionaires and billionaires will not be able to buy a single Bitcoin even if they want to. . So imagine how many bitcoins there would be if billionaires and millionaires couldn't afford to buy a bitcoin.