It would take at least 500 survivors to repopulate the earth (without creating major issues because of inbreeding) after an apocalypse.
Monowi village in USA has a population of 1 and the only resident runs a 5000-volume library and a tavern that draws regular customers from as far as 80 miles away.
Between 1960 and 2010, the world population rose from 3 billion to 6.8 billion. In other words, there has been more growth in population in the last fifty years than the previous 2 million years that humans have existed.
China’s population grows at a rate of 23,000 people per day.
Human beings are the only primates whose numbers are not in decline.
There are 12 U.S. cities with a population of 1. If they get killed it will be the first city with a 100% homicide rate.
Up to 25% of the population may have trouble distinguishing between right and left, even into adulthood.
0.5% of the world’s population owns 38.5% of its wealth. The bottom 66% of humanity account for just 3.3% of it.
If the entire world population of 6.9 billion lived in a single city as dense as Paris, it would only take up as much space as Arkansas, Mississippi and Louisiana.