CREATE TABLE table_20260 ("#" FLOAT, "Episode" CLOB, "Rating" CLOB, "Share" FLOAT, "Rating/Share  ( 18-49 ) " CLOB, "Viewers  ( millions ) " CLOB, "Rank  ( Timeslot ) " CLOB, "Rank  ( Night ) " CLOB, "Rank  ( Week ) " CLOB)

what rank has viewers at 6.45?
SELECT "Rank (Week)" FROM table_20260 WHERE "Viewers (millions)" = '6.45'
SELECT "Rank (Week)" FROM "table_20260" WHERE "Viewers (millions)" = '6.45'