SELECT COUNT("Directed by") FROM table_26737 WHERE "UK Ratings (BBC2 Rank)" = '2.27m (5)'
How many directors worked on the episode with 2.27m (5) is the ratings?
CREATE TABLE table_26737 (
    "Series No." real,
    "Episode No." real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "UK Ratings (BBC2 Rank)" text,
    "Original air date" text
)