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One has $$\sum_{n \leq x}\frac{n}{\operatorname{rad}n} = (1+o(1)) \, x \sqrt{\frac{2}{\log x \log \log x}} \exp\left((1+o(1))\sqrt{\frac{8\log x}{\log \log x}}\right) \ (x \to \infty),$$ according to user "Ofir Gorodetsky"'s detailed answer to a similar question to yours at Asymptotic behavior of a "strange" arithmetic function

The exp term grows faster than any power of $\log x$, so dividing by $\sqrt{\log x \log \log x}$ does nothing to change that.