How many letters does the top answer for “the quality of being productive or having the power to produce” have?

The most common answer is productiveness (14 letters).

Crossword clue: the quality of being productive or having the power to produce

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

productiveness 14 letters wn-def

the quality of being productive or having the power to produce

productivity 12 letters wn-def

the quality of being productive or having the power to produce