I believe there is an error in this question.
If, as it says, F(4) is the value of the hundreds digit, then F(1) is the value of the decimal digit of N.
Given that N is an integer, then F(1)=0.
F(1)=F(2)=F(3)=F(4)=F(5)=F(6)=0 --> N=0 and it is not a 6 digit integer. This contradicts the question stem.
Or am I missing something?
Please kudos if my post helps.