Potential of A Conducting Cube

Six identical conducting square plates are joined to make a cube.

One of these plates shown is insulated from adjacent plates at its edges with the help of a perfect insulating paint.

The shaded plate is connected with a battery of electromotive force $V$ and other plates are earthed as shown in the figure.

Find the potential at the center of the Cube.

If your Answer is of the form $\frac{V}{x}$ , where $x$ is an integer, enter $x$ .