# -*- coding: utf-8 -*- #寻找某个大数的最大质数 # 判断是否为质数,是质数返回1,否则返回0 def is_prime(num): limit = int(pow(num,0.5)) i = 2 while 1: if num % i == 0 or i > limit: break i += 1 if i > limit: return 1 return 0 number = 600851475143 prime = 2 # 主程序 while not is_prime(number): while number % prime == 0: number /= prime prime += 1 print number