Is Sonic a Fortune 500 company?

I'm curious to know if Sonic, the well-known restaurant chain known for its burgers and shakes, is actually a Fortune 500 company. I've seen their franchises all over the country, and they seem to be doing quite well. But, is Sonic large enough to be included in the prestigious Fortune 500 list of the largest American companies by revenue? It would be interesting to find out if they've reached that level of success and recognition in the industry.