Find the missing number in the series? 4, 18, ?, 100, 180, 294, 448

Take a Look at this series :

$23$ -  $22$ =  8 - 4 = 4  

$33$ -  $32$ = 27 - 9 = 18 

$43$ -  $42$ = 64 - 16 = 48  

$53$ -  $52$ = 125 - 25 = 100  

$63$ -  $62$ = 216 - 36 = 180 

$73$ -  $72$ = 343 - 49 = 294 

$83$ -  $82$ = 512 - 64 = 448