Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_11253290_2 ( viewers__millions_ VARCHAR, rank__week_ VARCHAR )

### Question ###
How many viewers (millions) were there for rank (week) 20?

### Accurate SQL ###

SELECT COUNT(viewers__millions_) FROM table_11253290_2 WHERE rank__week_ = "20"