The angular momentum(AM) of a planet is derived from the AM of the whole system at it’s formation. If it’s too great, the system won’t form, and the greater it is, the longer it takes to form. So there’s an upper limit to the spin of the whole system from the beginning. The planets usually end up round. That wouldn’t happen, if there was a significant centrifical force at the equator. It would be an oblate spheroid. That pic does look like the equitorial radius might be ~17% greater than the polar radius though. That’s if it’s a pic of the planet and it’s not been distorted by a pic edit. In that case, the gravitational force at the surface would be would be 1.8, instead of 2.2.
2.2(1-0.17)=1.8
Depending on the pic...
So, what’s the formula for gravitational force?
So what about Godebert's question? What effect would this have on atmospheric pressure, assuming an Earth-like atmosphere since it's supposed to be habitable.
That would indeed suggest that for a larger body generally the spin could indeed be much greater than for a smaller body...since if it's greater, the body would have less time to become tidally locked.
So...if this thing is rapidly rotating, and it has a nuclear core, along with the 13 day years for seasons, perhaps the estimate isn't too far-fetched, as its day/night temperatures would be less extreme than on earth (obviously the unknown atmosphere factors in), near the equator its gravity would be more reasonable, and it'd probably have a very powerful magnetic field to protect it from many of the solar effects.
That pic does look like the equitorial radius might be ~17% greater than the polar radius though. That’s if it’s a pic of the planet and it’s not been distorted by a pic edit. In that case, the gravitational force at the surface would be would be 1.8, instead of 2.2.
Granted the caveats, that's a huge difference. One that begins to put it down into the plausible range.