7, 11, 21, 4, 49, 263, 64, 512, 144, 5, 12, 9

I could go on for 3.14^2 with numbers like these but what I'm asking is why are thee numbers so fucking relevant? We don't count by simply 1 or 3, it's always a dozen eggs, seven keys, 360 days, 512 megabytes, 49 chromosomes, 11 cards, 4 suits.

What is the scientific mathematical physical biological reasoning behind these weird numbers?