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_13836704_7 ( international_passengers VARCHAR, rank VARCHAR )

### Question ###
What is the total number of passengers of the airport ranked 15?

### Accurate SQL ###

SELECT international_passengers FROM table_13836704_7 WHERE rank = 15