That is not right. There are 1.33 × 10¹⁸ photons
.
Energy of one photon
E = hf = hc/λ = (6.626 × 10⁻³⁴ J·s × 2.998× 10⁸ m·s⁻¹)/(633 × 10⁻⁹ m)
= 3.138 × 10⁻¹⁹ J
Number of photons
No. of photons = 0.418 J × (1 photon/3.138 × 10⁻¹⁹ J) = 1.33 × 10¹⁸ photons
