What is the next number of the following series - 173, 327, 491, 184, 276, 361, 214, 346, ??

Answer 1

173,  327, 491 -->  (1+3) (7+2) (3+7=10 --> 1+0 =1) --> 491
184, 276, 361 - -> (1+2) (8+7=15 - > 1+5 = 6) (4+6=10 --> 1+0=1) --> 361 
214, 346, --> (2+3) (1+4) (4+6=10 --> 1+0 =1) --> 551

Answer is 551

Answer 2

(173 + 327 ) - 491 = 9
( 184 + 276) - 361 = 99
( 214 + 346 ) - (-499) = 999
The answer is -499