17:03
I was only wondering about the action on the spectrum, not about any ring structure. I agree having a ring structure would make it easier.
You can also ask for an action of $\mathbb{Z}_p^\times$ on $E(n)_p$, the $p$-completion of $E(n)$.
At $p=2$, you'd want the $\{\pm1\}\subset \mathbb{Z}_{(2)}^\times$ action to pick of the real Johnson-Wilson spectrum of Hu-Kriz.
For comparison, $TMF_{(p)}$ (periodic tmf localized at $p$) does admit a $\mathbb{Z}_{(p)}^\times$-action (through $E_\infty$-maps), by Lurie-theory.