Yes, HAPHTAROTH is a Scrabble word!

Letter values in Scrabble US: H 4, A 1, P 3, H 4, T 1, A 1, R 1, O 1, T 1, H 4.

Is it a valid word?

HAPHTAROTH is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a short selection from the Prophets read on every Sabbath in a Jewish synagogue following a reading from the Torah

Not playable in Scrabble US: HAPHTORAH.