number theory prove for all $k \in \mathbb{Z\_{\geq 0}}$ , $2^{2^{6k}\cdot4}\equiv 2^4\pmod{19}$

***attempt***:

$$2^{2^{6k}\cdot4}\equiv 2^4\pmod{19}$$
we can rewrite the equation
$$(2^4)^{2^{6k}}\equiv 2^4\pmod{19}$$

How I can continue from there to apply the Euler's theorem