Edges in a graph with no triangles

Discrete Mathematics Level 5

A simple graph $G$ has 200000 edges and for any 3 vertices $v,w,x,$ at least one of the edges $vw, wx, xv$ is not present in $G.$ What is the least number of vertices that $G$ can have?

Details and assumptions

A simple graph does not have multiple edges between vertices, or self loops.