#~ largest number small from 20 is 19 and its prime. we must collect all prime numbers as:
#~ 19,17,13,11,7,5
#~ and small from 20 and the largest even of 2 and 3 are 16 and 9.
#~ so we must multiply all of them its the result of this question.
print 19*17*16*13*11*9*7*5
