If so, what are some of the estimates? I'm interested in total number of homo sapiens.
107 Billion
(107,000,000,000)
It’s fairly easy to estimate, as the amount of the oldest Homo Sapiens would only be several tens of thousands at a time, meaning that even without historical records, the amount of humans that lived between the first humans and 6000 years ago is known to be very low compared to modern amounts (probably 25,000,000-50,000,000 humans ever lived in that 300,000 year period. It was only until the early 1800’s that humanity reached 1 billion in population at any given time. The vast majority of the 107 billion estimate are from humans that have lived in the most recent millennium.