How many servers does Wikipedia have?

As of November 2014, Wikipedia had over 4,652,535 articles in English, over 1,774,000 in German, over 1,560,000 in French, over 1,155,000 in Italian, over 1,137,000 in Spanish, and a combined total of over 34,290,907 articles.

If you go to Wikipedia's home page you will see a list of different languages by number of articles.

For a more exact number go to the Wikipedia page called Wikipedia:Size of Wikipedia.