It does look like Acanthastrea echinata. I would move it farther away from any corals of other species. Echinatas are quite aggressive and will reach out and dissolve other corals with mesenteric filaments.
For example, the coral right behind it used to be classified as an Acanthastrea too, and is still called an 'Acan' in the hobby. However it's proper scientific name is currently Micromussa lordhowensis, not Acanthastrea at all, and the echinata will definitely murder it if it gets the chance.