Problem #139
Sum Me
Let F(n) = sum of all divisors of n.
Find the sum of all n such that F(n) = 2*n and 1<=n<=5 * 10^{35}
Report your answer modulo 10^9+7.
Let F(n) = sum of all divisors of n.
Find the sum of all n such that F(n) = 2*n and 1<=n<=5 * 10^{35}
Report your answer modulo 10^9+7.