The aircraft in question is similar to a quadcopter.
Yes. 490 + 490 + 490 + 490 = 1960. For practical purposes, the thrusts from individual rotors do not interfere constructively or destructively: they neither cancel each other out, nor do they help each other. This case is pretty much the same as multiple propellers mounted on a fixed wing.
The situation becomes more complicated only if some rotors overlap, or are coaxial.