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_1620397_2 ( series_sorted VARCHAR, released VARCHAR )

### Question ###
Name the total number of series sorted for when released is april 2010

### Accurate SQL ###

SELECT COUNT(series_sorted) FROM table_1620397_2 WHERE released = "April 2010"