You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Comcast

Context:
In 2001, Comcast announced it would acquire the assets of the largest cable television operator at the time, AT&T Broadband, for US$44.5 billion. The proposed name for the merged company was "AT&T Comcast", but the companies ultimately decided to keep only the Comcast name. In 2002, Comcast acquired all assets of AT&T Broadband, thus making Comcast the largest cable television company in the United States with over 22 million subscribers. This also spurred the start of Comcast Advertising Sales (using AT&T's groundwork) which would later be renamed Comcast Spotlight. As part of this acquisition, Comcast also acquired the National Digital Television Center in Centennial, Colorado as a wholly owned subsidiary, which is today known as the Comcast Media Center.

Question:
When Comcast purchased AT&T Broadband, how many customers did they service?

22 million