Correct primality certification?

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With pari/gp , I tried to prove the primality of the number $$63638089207891963635134908^{1024}+1$$

I applied the Pocklington test and the output was

? n=63638089207891963635134908^1024+1;
? factorint(n-1)
%19 =
[          2 2048]

[          7 1024]

[      39857 1024]

[ 1803629963 1024]

[31616009371 1024]

? isprime(n,1)
%20 =
[    2 3 1]

[    7 2 1]

[39857 2 1]

Apparently, only the three smaller prime factors were used in the certification. I wonder why this certification is valid because apparently, $A=(2^2\cdot 7\cdot 39857)^{1024}$ is used which is even smaller than the fourth root of $n$.

Is there a variant of the Pocklington test justifying this certification with only $3$ of the $5$ prime factors ? Or what else do I miss ?