Yes, CHARACTERISTICS is a Scrabble word!

Letter values in Scrabble US: C 3, H 4, A 1, R 1, A 1, C 3, T 1, E 1, R 1, I 1, S 1, T 1, I 1, C 3, S 1.

Is it a valid word?

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

a prominent attribute or aspect of something
a distinguishing quality
the integer part (positive or negative) of the representation of a logarithm; in the expression log 643 = 2.808 the characteristic is 2
any measurable property of a device measured under closely specified conditions

Also: device characteristic.