The Teeth of the Hydra

Jason fought the Hydra to gain the legendary Golden Fleece. The Hydra had 7 heads with 24 teeth in each mouth. Each time Jason cut off one of the heads, 2 new ones grew back.
When Jason finally stabbed the Hydra in its heart and slew it, he had cut off 13 of its heads. The king of Persia gathered up all the Hydra's teeth from all of the heads (those cut off and those still attached to the body) and planted them. The next morning an army of skeletons grew out of the ground. Each tooth produced 7 skeleton warriors. How many skeletons did Jason and his men have to fight?