The bigger factor is the distance. Radio (like most radiant sources) fall off proportional to the inverse of the square of the distance from the source.

In the case of cell phone radiation, using 900Mhz makes the calculation easy. A tower transmitting about a kilometer away at 10KW reaches you with about 0.0005 mW/cm². A 2W trasmitter at one meter away means you're sucking up close to 0.1 mW/cm². At one inch, you're getting pretty much getting all 2W, about 75 mW/cm².

So no, radiation exposure from a cell tower is no where near what you're getting from having it inches away from you. Yes, towers transmit stronger signals than phones, but one also doesn't tend to press one's head to a tower panel. In the case of radio, proximity is the key factor to how much exposure you're getting.