Earths angular velocity........?

The acceleration of gravity is 9.81 m/s^2 right? The centripetal force required to keep an object in uniform circular motion is F = m v^2 / R = m w^2 R. (w = v/R = angular velocity) So the centripetal acceleration is a = w^2 R. So if 9.81 is bigger than a, then you fall to the ground. However, if 9.81 is less than a, then you are flung off the spinning earth. Of course this happens first for the largest radius, the equator.