The answer to this question would depend on the set laws of the universe, and would also depend on whether these particle were bosons or fermions and whether they had rest mass or not. Also keep in mind that a large mass will curve spacetime around it, for practical purposes a black hole is such a thing. Regardless even if we assumed the existence of such particles - and particles generally come in discreet values - I think an absolute answer to this would require and understanding of quantum gravity which is not yet available. From a stricly mathematical standpoint of course, the answer would depend on which of your three variables - particle count, particle size and particle mass - approached infinity faster, and that combination could yield either a finite mass, an infinite mass, or a zero mass.

Green is a wasted color, and inefficient as it serves no useful purpose other than to heat the planet up, we should put a bunch of thin green filters between us and the sun to block out some of it... and I don't like orange.