How many bitcoin whales exist, and how many BTCs they have
It is possible to quantify the whales of BTC; to do so, just consult Bitinfocharts.

The chart tells us that:
The top 100 wealthy hold 15.02% of the total bitcoin supply, or 2.8 million BTC for $133 billion;
The top 10 addresses have 6.04% of the wealth,
The top 100 addresses have 15.02% of the wealth;
There are over 2 million addresses that have at least $10,000 in bitcoin.