If you are 50 years old this year, then my answer is 10 bitcoins. In the future, bitcoin will definitely be worth more than 1 million US dollars each. According to conservative calculations, one bitcoin is 1 million US dollars, and 10 bitcoins are 10 million US dollars. The 10 bitcoins you hold are equivalent to the lifetime of a working elite!
If you are 40, then 5 is enough.
If you are 30 then 2 is enough
If you are 20 years old then 0.5 is enough
If you are 10 years old, then 0.36 is enough.
If you are 30-40 years old and hold 20 bitcoins, you will have a free life.
If you hold 100 bitcoins, the earth will be your village. Come on, fellow bitcoiners! #BTC