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_11656578_2 ( area_km²__1998_ VARCHAR, no_of_communes VARCHAR )

### Question ###
What's the area of the voivodenship with 51 communes?

### Accurate SQL ###

SELECT area_km²__1998_ FROM table_11656578_2 WHERE no_of_communes = 51