$16p+1$ is perfect cube so let is be $x^3$
So $x^3-1 = 16p$
Or $(x-1)(x^2+x+1) = 16p$
Now $x^2+x+1$ is is odd so $16| x-1$
So $(x-1) = 16m$ and $x^2+x+1 = n$ where m and n are odd
So p = mn
As p is odd $m = 1, n = p$ or $m = p, n= 1$
n= 1 gives $x^2+x+1 = 1 $ or x = 0 which is not possible
so m= 1 and x= 17 giving n = 307 wihich is a prime
so $p = 307$
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