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_56 (population_density__per_km²_ VARCHAR, population__2006_ VARCHAR)

### Question ###
What population density (per km) that has 84 as the population (2006)?

### Accurate SQL ###

SELECT population_density__per_km²_ FROM table_name_56 WHERE population__2006_ = "84"