Prime numbers in large number

05AB1E (legacy), 3 bytes

Œʒp

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Substrings of the input that are prime.

Perl 6, 28 bytes

{grep &is-prime,+«m:ex/.+/}

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The :ex ("exhaustive") flag to the match operator m makes it return every possible match of .+ (ie, every substring of one or more characters), even overlapping ones. The hyperoperator +« turns that list of Match objects into numbers, which are then filtered for primeness by grep &is-prime.

Python 2, 66 65 bytes

P=k=1
n=input()
while~n+k:
 if`k`in`n`>0<P%k:print k
 P*=k*k;k+=1

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