Lets arrange the letters alphabetically = AAANRSTTW
Words starting with A = 8!/(2!*2!) = 10080
Words starting with N = 8!/(3!*2!) = 3360
Words starting with R = 8!/(3!*2!) = 3360
Words starting with SA = 7!/(2!*2!) = 1260
Words starting with SN = 7!/(3!*2!) = 420
Words starting with SR = 7!/(3!*2!) = 420
Words starting with ST = 7!/(3!) = 840
Words starting with SWAA = 5!/(2!) = 60
Words starting with SWAN = 5!/(2!*2!) = 30
Words starting with SWAR = 5!/(2!*2!) = 30
Words starting with SWATAA = 3! = 6
Words starting with SWATANA = 2! = 2
Words starting with SWATANR = 2! = 2
Words starting with SWATANTA = 1 = 1
And next word is SWATANTRA so + 1