Which series # had 0.645 U.S. viewers(millions)?
CREATE TABLE table_26808178_3 (
    series__number INTEGER,
    us_viewers__millions_ VARCHAR
)
SELECT MAX(series__number) FROM table_26808178_3 WHERE us_viewers__millions_ = "0.645"
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: Which series # had 0.645 U.S. viewers(millions)? ### Input: CREATE TABLE table_26808178_3 (
    series__number INTEGER,
    us_viewers__millions_ VARCHAR
) ### Response: SELECT MAX(series__number) FROM table_26808178_3 WHERE us_viewers__millions_ = "0.645"