OK, it's been a while since I tossed out a Bible inconsistancy. This one is from Numbers 2:32 and 3:40-51.
Numbers 2 says that there was 600,000 males in Israel over age 20. Numbers 3 says that there were just over 22,000 firstborn males, including those under 20 years old. This means that the Israelite women each had an average of at least 27 boys. Arguably that number could be doubled if the total census had included all males not just those over 20. Say 50 boys to a mother. Then add the girls and voila, each Israelite woman average about 100 kids.
I know that there have been attempts to explain this obvious imposssibilty, but inevitably they require adding to the clearly written text.