Table: scotland_counties_1890_1975
Columns: county
area_acres
area_km
population
population_density_per_km_2

Question: What is the lowest population of the county with an area (km²) of 565.39 and a population density less than 23.54?
SQL: SELECT MIN("population") FROM scotland_counties_1890_1975 WHERE "area_km" = 565.39 AND "population_density_per_km_2" < 23.54