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_name_21 (losses INTEGER, points VARCHAR, goals_against VARCHAR, goal_difference VARCHAR)

### Question ###
How many losses when goals against are more than 17, goal difference is more than 2 and points are more than 5?

### Accurate SQL ###

SELECT AVG(losses) FROM table_name_21 WHERE goals_against > 17 AND goal_difference < 2 AND points > 5