Table schema:
CREATE TABLE table_name_39 (density__inhabitants_km_2__ INTEGER, city VARCHAR, area__km_2__ VARCHAR, altitude__mslm_ VARCHAR)

Question: What is the lowest density of alessandria where the area is bigger than 16.02 and altitude is less than 116?
SQL: SELECT MIN(density__inhabitants_km_2__) FROM table_name_39 WHERE area__km_2__ > 16.02 AND altitude__mslm_ < 116 AND city = "alessandria"