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_21963 ( "Voivodeship after 1569" text, "Capital" text, "Year established" real, "Number of powiats" text, "Area (km\u00b2) in 1590 (Lithuanian) Category:Articles with Lithuanian-language external links" real )

### Question ###
What is the latest year established that had 5 powiats?

### Accurate SQL ###

SELECT MAX("Year established") FROM table_21963 WHERE "Number of powiats" = '5 powiats'