what's the next number??-Fun Game

QUESTION: 
what's the next number?? 
1, 2, 6, 42, 1806, ? 
the 6th number is the password to the attached excel file. 
add your name in the list if you got the correct answer and pass it on!..

Just do it. .. 

if u get the correct answer send us your name and Ans

Thanks & regards

Karthikeyan.K

clik here

Download the excel file