How many people were there by the time of the Tower of Babel?
No exact figure is given for the population at the Tower of Babel. By that time, a couple hundred years after Noah's three sons, the race had not multiplied into millions, yet there were already quite a few people, all of one language and one blood, gathered in Shinar.
Les explains that between Noah and Abraham there are about 400 years, and in the middle of that period came the Tower of Babel. He notes the race had not yet multiplied into millions upon millions, but there were already quite a few after just a couple hundred years from Noah's three sons. The whole human race, still of one language and one blood, met in the plains of Shinar, in Mesopotamia in the Euphrates River Valley, and built the Tower. Under Nimrod, Satan instituted all pagan and mythological religions there. By Abraham's time, a couple hundred years after the Tower, at 2000 B.C., the whole then-known human race was steeped in idolatry or mythology. Out of that race, God found one man with a spark of faith.