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Totient Sum

 Published on Saturday, 15th June 2013, 01:00 pm and solved by 764
Difficulty: Level 28 [71%]

Problem 432

Let $S(n,m) = \sum\phi(n \times i)$ for $1 \leq i \leq m$. ($\phi$ is Euler's totient function)
You are given that $S(510510,10^6)= 45480596821125120$.

Find $S(510510,10^{11})$.
Give the last $9$ digits of your answer.



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