smc

This equation is $r^6{e}^{6\theta i}=2^6{e}^{(\pi \pm 2k\pi )i}$. Solving in the usual way, $r=2$ and $\theta \in \{\pm 30^{\circ },\pm 90^{\circ },\pm 150^{\circ }\}$. Thus there are only two solutions with positive real part, and they are conjugates, so their product is $r^2=4$ which is $\boxed{4}$