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_23575917_4 (episode VARCHAR, first_broadcast VARCHAR)

### Question ###
What is the episode number that was first broadcast on 3 September 2010?

### Accurate SQL ###

SELECT episode FROM table_23575917_4 WHERE first_broadcast = "3 September 2010"