Genesis 26:4
"I will make your descendants as numerous as the stars in the sky and will give them all these lands, and through your offspring all nations on earth will be blessed"

Here God tells Isaac that his descendents (Hebrews) will be as numerous as the stars. There are ten billion trillion KNOWN stars in the sky so there will have to be 10,000,000,000,000,000,000,000 Jewish people born to fulfill this prophecy.