Suppose pritom has N chocolate, in each of the way he chose \(X1,X2,X3...\) friends to distribute the chocolate.
for \(Xi\) number of chosen friends each of the friends will get \(N/Xi\) amount of chocolate each. Since the number of chocolate each friend gets must be an integer so \(Xi\) must be a divisor of N.

so every \(Xi\) must be a divisor of N. finally we can conclude that the answer will be the total number of divisort of N.

time complexity : O(sqrt(N))