You will need the magic number of 20 bitcoins to retire COMFORTABLY in 20 years.
20 bitcoin too small to retire in 20 years. 20 bitcoin might be worth if bitcoin prices could touch $100,000 in 20 years.
It depends on where you live. If you live a simple life, $1 million is more than enough to live comfortably.
I think wherever you live $1 million was a very decent. but maybe if in asian, the value is more than enough.