Four point charge, each of +q, are rigidly fixed at the four corners of a square planar soap film of side 'a'. The surface tension of the soap film is $$\gamma$$. The system of charges and planar film are in equilibrium, and $$a = k\left[\frac{q^2}{\gamma}\right]^{\frac{1}{N}}$$, where 'k' is a constant. Then N is