The factorial of a number

Calculate the value of:

$4!$
$6!$
$(8-3)!$
$(2^3)!$
$2^{3!}$

$4! = 4\cdot3\cdot2\cdot1 = 24$
$6! = 6\cdot5\cdot4\cdot3\cdot2\cdot1 = 720$
$(8-3)! = 5! = 5\cdot4\cdot3\cdot2\cdot1 = 120$
$(2^3)! = 8! = 8\cdot7\cdot6\cdot5\cdot4\cdot3\cdot2\cdot1 = 40.320$
$2^{3!}= 2^{3\cdot2\cdot1}=2^6=64$

$4! = 24$
$6! = 720$
$(8-3)! = 120$
$(2^3)!= 40.320$
$2^{3!}=64$