Given,
f(m⋅n)=f(m)⋅f(n)
Taking m=1
⇒f(1⋅n)=f(1)⋅f(n)
⇒f(1)=1
Now taking m=3&n=3 we get,
f(9)=f(3)×f(3),
So, (f(3),f(9)) have two possibility (1,1)&(3,9)
Now taking m=2&n=1 we get,
f(2⋅1)=f(2)⋅f(1)
Now here f(1)=1, so f(2) can take all 6 numbers,
Similarly, for f(5)&f(8) there will be 6 ways each,
So, total possible function will be, =1×6×2×6×6×1=432