This has turned into a complicated study, and is definitely a work in progress. However I thought there is value in posting what I have so far, so here we go.
Exodus 12:37 And the children of Israel journeyed from Rameses to Succoth, about six hundred thousand on foot [that were] men, beside children.
600,000 men? If there were 600,000 men this would imply that each man had a wife and some children, thus the number can be closer to 3 million total people. There are a few arguments against this number, both from the secular community and the biblical.