Table schema:
CREATE TABLE table_name_53 (gdp_per_capita__us INTEGER, literacy__2003_ VARCHAR, area__km²_ VARCHAR)

Question: Which GDP per capita (US$) (2004) has a Literacy (2003) of 90%, and an Area (km²) of 1247689.5?
SQL: SELECT AVG(gdp_per_capita__us) AS $___2004_ FROM table_name_53 WHERE literacy__2003_ = "90%" AND area__km²_ = 1247689.5