If we assume that there is a new generation every twenty-five years, an ancestor born 1,000 years before you would be 40 generations removed from you. You would have 2,199,023,255,550 (that’s 2 trillion, 199 billion, 23 million, 255 thousand, 550) unique ancestors born in the previous 40 generations, assuming no overlap (that is, none of your ancestors were cousins to other ancestors).
https://blog.eogn.com/2018/01/26/how...s-do-you-have/