import time import math start_time = time.time() result = reduce(lambda x, y: x * y, range(1, 10001)) end_time = time.time() print '%f s' % (end_time - start_time ) print result start_time = time.time() result = math.factorial(10000) end_time = time.time() print '%f s' % (end_time - start_time ) print result