What number episode had 5.74 million viewers? 
CREATE TABLE "table1_12976038_1" (
  "episode_num" real,
  "series_num" real,
  "title" text,
  "director" text,
  "writer" text,
  "original_airdate" text,
  "viewers_in_millions" text
);
SELECT "episode_num" FROM "table1_12976038_1" WHERE "viewers_in_millions"='5.74';