How many letters does the top answer for “wrote father sergius” have?

The most common answer is tolstoy (7 letters).

Crossword clue: wrote father sergius

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

tolstoy 7 letters wd-fact-v3

Russian author remembered for two great novels (1828-1910)

author of father sergius 50% similar → tolstoy

wrote father brown 50% similar → chesterton

wrote fathers and sons 50% similar → turgenev