Yes, TELLERS is a Scrabble word!

Letter values in Scrabble US: T 1, E 1, L 1, L 1, E 1, R 1, S 1.

Is it a valid word?

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

United States physicist (born in Hungary) who worked on the first atom bomb and the first hydrogen bomb (1908-2003)
an official appointed to count the votes (especially in legislative assembly)
an employee of a bank who receives and pays out money
someone who tells a story

Also: edward teller, vote counter, bank clerk.