Over the last month 66,560,159 people have played the Sims Social on Facebook.

That is more than double the audience who tuned in for Ashton Kutcher’s recent debut on the hit sitcom “Two and a Half Men.” It is roughly twice the number of copies of “The Catcher in the Rye” sold during the last 60 years. And it is about 20 million more people than have ever purchased Pink Floyd’s 1973 classic “The Dark Side of the Moon.”

If you’re over 25 and haven’t had school-age children in the last decade, or ever, the Sims may not mean much to you. But plenty of others (meaning young people and parents of elementary and middle-school children) know all about it. They wouldn’t be surprised to hear that the Sims series has sold more than 140 million retail copies since its introduction 11 years ago. The only video game franchise that’s been more popular is Nintendo’s Mario. And now the Sims, made by Electronic Arts, has come to the world’s dominant social network, that staple of the daily lives of hundreds of millions of people around the world. I imagine that a few executives at Zynga headquarters in San Francisco are beginning to fret.

Zynga, of course, is the Wall Street darling that first identified and exploited the opportunity to lure millions of people into clicking on their farms and mafias every day on Facebook when they would otherwise be reading updates about the feeding habits of their ex-roommate’s infant. Zynga is the maker of what remains the No. 1 application on Facebook, CityVille.