Estimating the following two numbers should be interesting. The first number will tell you why radio engineers do not need to worry much about photons! The second number tells you why our eye can never 'count photons',even in barely detectable light.
$(a)$ The number of photons emitted per second by a Medium wave transmitter of $10\; kW$ power,emitting radiowaves of wavelength $500\; m$.
$(b)$ The number of photons entering the pupil of our eye per second corresponding to the minimum intensity of white light that we humans can perceive $(10^{-10}\; W m^{-2})$. Take the area of the pupil to be about $0.4\; cm^2$,and the average frequency of white light to be about $6 \times 10^{14}\; Hz$.

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(N/A) Power of the medium wave transmitter,$P = 10\; kW = 10^4\; W = 10^4\; J/s$.
Hence,energy emitted by the transmitter per second,$E = 10^4\; J$.
Wavelength of the radio wave,$\lambda = 500\; m$.
The energy of a single photon is given by $E_1 = \frac{hc}{\lambda}$.
Where,$h = 6.6 \times 10^{-34}\; Js$ and $c = 3 \times 10^8\; m/s$.
$E_1 = \frac{6.6 \times 10^{-34} \times 3 \times 10^8}{500} = 3.96 \times 10^{-28}\; J$.
Let $n$ be the number of photons emitted per second.
$n = \frac{E}{E_1} = \frac{10^4}{3.96 \times 10^{-28}} \approx 2.525 \times 10^{31} \approx 3 \times 10^{31}$ photons/s.
Since the number of photons is extremely large,the discrete nature of energy can be ignored,and the wave can be treated as continuous.
$(b)$ Intensity of light,$I = 10^{-10}\; W m^{-2}$.
Area of the pupil,$A = 0.4\; cm^2 = 0.4 \times 10^{-4}\; m^2$.
Frequency of white light,$\nu = 6 \times 10^{14}\; Hz$.
Energy of one photon,$E_p = h\nu = 6.6 \times 10^{-34} \times 6 \times 10^{14} = 3.96 \times 10^{-19}\; J$.
Total energy incident on the pupil per second,$E_{total} = I \times A = 10^{-10} \times 0.4 \times 10^{-4} = 4 \times 10^{-15}\; J/s$.
Number of photons entering the pupil per second,$n = \frac{E_{total}}{E_p} = \frac{4 \times 10^{-15}}{3.96 \times 10^{-19}} \approx 1.01 \times 10^4$ photons/s.
This number is large enough that the human eye cannot perceive individual photons.

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