Yes, ANTEATERS is a Scrabble word!

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

Is it a valid word?

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

toothless mammal of southern Africa and Asia having a body covered with horny scales and a long snout for feeding on ants and termites
any of several tropical American mammals of the family Myrmecophagidae which lack teeth and feed on ants and termites
nocturnal burrowing mammal of the grasslands of Africa that feeds on termites; sole extant representative of the order Tubulidentata
small Australian marsupial having long snout and strong claws for feeding on termites; nearly extinct
a burrowing monotreme mammal covered with spines and having a long snout and claws for hunting ants and termites; native to New Guinea
a burrowing monotreme mammal covered with spines and having a long snout and claws for hunting ants and termites; native to Australia

Also: scaly anteater, new world anteater, ant bear, orycteropus afer, banded anteater, myrmecobius fasciatus, spiny anteater.