How many viewers were there for airdate is 22 october 2009?
CREATE TABLE table_73658 (
    "Episode no." real,
    "Airdate" text,
    "Viewers" real,
    "BBC Three weekly ranking" text,
    "Cable rank" text
)
SELECT MAX("Viewers") FROM table_73658 WHERE "Airdate" = '22 October 2009'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: How many viewers were there for airdate is 22 october 2009? ### Input: CREATE TABLE table_73658 (
    "Episode no." real,
    "Airdate" text,
    "Viewers" real,
    "BBC Three weekly ranking" text,
    "Cable rank" text
) ### Response: SELECT MAX("Viewers") FROM table_73658 WHERE "Airdate" = '22 October 2009'