\[ \phi(1) \left \lfloor \dfrac {63}{1} \right\rfloor + \phi(2) \left \lfloor \dfrac {63}{2} \right\rfloor + \phi(3) \left \lfloor \dfrac {63}{3} \right\rfloor + \cdots + \phi(63) \left \lfloor \dfrac {63}{63} \right \rfloor = \, ? \]

**Notations:**

- \(\phi(\cdot) \) denotes the Euler's totient function.
- \( \lfloor \cdot \rfloor \) denotes the floor function.

**Bonus:** Generalize this for \( \displaystyle \sum_{k=1}^n \phi(k) \left \lfloor \dfrac n k \right \rfloor \).

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