Find the next number in the series given 18, 90, 450, 2250, ?

The given number series is 18, 90, 450, 2250, ?

18

18 x 5 = 90

90 x 5 = 450

450 x 5 = 2250

2250 x 5 = 11250

Hence, the next number in the given series is 11250.