roperties o prime if plab than either pla or pb(or both) there an infinite number of prime numbers Prime number theorem letπ(x) denote the number of prime numbers≤ then 再父 →> (21 Properties of prime • if p|ab than either p|a or p|b (or both) • there an infinite number of prime numbers • Prime number theorem: – let (x) denote the number of prime numbers  x, then 1 ln ( ) lim = → x x x x 