$200,000,000,000 scam in Bitcoin ??

[First77]

21,000,000 bitcoins x $20,000 = $420,000,000,000

How did market capitalization of Bitcoin was shown as $650,000,000,000 ??  

Rule says not more than 21,000,000 Bitcoins will mined

[OmegaStarScream]

The marketcap is based on the current supply which is 16.8 million and not 21m so the marketcap is currently $200 Billion. The $650B you're currently reading is most likely the one of all cryptos combined.

[cosmoo]

21,000,000 bitcoins x $20,000 = $420,000,000,000

How did market capitalization of Bitcoin was shown as $650,000,000,000 ??  

Rule says not more than 21,000,000 Bitcoins will mined

650 billions it is  market capitalization of all cryptocurrencies, not just Bitcoin. And where you get the price of 20,000 USD? LOL

[1NV3ST0NM3]

21,000,000 bitcoins x $20,000 = $420,000,000,000

How did market capitalization of Bitcoin was shown as $650,000,000,000 ?? 

Rule says not more than 21,000,000 Bitcoins will mined

You have been a bit wrong in calculation my friend. Current supply of bitcoin is just around 16,812,450 BTC while the price which floats now is near about 11811. Bitcoin until now hasn't even gone passed 300 when it comes to the maximum market cap. Which obviously went when it touched the price of as you said 20k or to be more price $19.6K. So chill out the capitalization you are talking about which obviously is show on the top of coinmarketcap is of all the cryptocurrencies combined.