Sun surface — UPSC IFoS 2020 Physics PYQ

Each square meter of the Sun's surface radiates energy at the rate of 6{\cdot}3 \times 10^7\text{ J/m}^2\text{ /s} and Stefan constant is 5{\cdot}669 \times 10^{-8}\text{ W/m}^2\text{ /K}^4. Find the temperature of the Sun's surface. Assume that the Stefan's law applies to the radiation.