Clark Kent isn’t a genius, is he?

Well, in Superman (1978), he spends a long period of time being educated by the hologram of his late father, Jor-El. Given how advanced Kryptonian science and technology was in comparison with Earth's, it's safe to assume that Superman possesses a significantly greater level of scientific knowledge than most humans. He's undoubtedly highly intelligent anyhow, but possessing knowledge millenia in advance of the rest of the population is bound to give one certain natural advantages.