[tex]\displaystyle\bf\\N = 2^{2n} + 2^{2n+3} + 2^{2n+4}\\\\N = 2^{2n} + 2^{2n}\times2^3 + 2^{2n}\times2^4\\\\\textbf{Dam factor comun pe }~2^{2n}\\\\N=2^{2n}(1+2^3+2^4)\\\\N=2^{2n}(1+8+16)\\\\N=2^{2n} \times25\\\\N=\Big(2^{n}\Big)^2 \times5^2\\\\\boxed{\bf~N=\Big(2^{n}\times5\Big)^2=pp}[/tex]