How to prove $\sum\frac1{n^p}$ converges only for $p>1$?

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Prove $\sum\frac1{n^p}$ converges only for $p>1$.

For this I need to prove that for $p>1$ and some $n>N\in\mathbb{N}$ $$\frac1{n^p}\le\frac1{p^n}$$

Then I can show that geometric series on RHS is an upper bound. But I am not able to prove this step.

Edit: Above inequality doesn't work as pointed out in the comments. Is there a way to bound this series by some geometric series.