Sublinear algorithm for $\sum_{i = 1}^n i \cdot \varphi (i)$

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I am trying to evaluate the sum $\sum_{i = 1}^n i \cdot \varphi (i)$ for large values of $n$, and therefore I need a sublinear algorithm for this. The summation of the totient function alone $\sum_{i = 1}^n \varphi (i)$ indeed has sublinear algorithms mentioned here. But the required sum here is different.

The progress I have made thus far is to show that $i \cdot \varphi (i) = \varphi(i^2)$ and therefore the sum may be rewritten (in perhaps a simpler form for summation):

$$\sum_{i = 1}^n i \cdot \varphi (i) = \sum_{i = 1}^n \varphi(i^2)$$

Is it possible to evaluate this sum in sublinear time?