Many galaxies appear to have supermassive black holes in their centers powering active galactic nuclei (also called AGN). The Schwarzschild radius of these supermassive black holes can be estimated in part by watching for changes in the brightness of the surrounding AGN and measuring the timescale of those changes. Assume we observe an AGN and determine it varies with a timescale of 7.39 minutes, which implies a Schwarzschild radius on the order of 1.33×1011 meters. Estimate the mass of this supermassive black hole.