I don't get any error when I try to run your file. But I also disagree with your idea of line 13. I say line 13 is

if($numInput % $divider == 0){
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That line has an error because $divider is uninitialized when you try to use it as the divisor in a mudulus operation. I do think you should use warnings; rather than have -w in line one ... the -w is a subset and I suspect would give you more information about this situation..

It seems like you actually intend to determine whether the input number is odd or even. No need. You can collapse that five lines of code into a simple expression:

my $half = int( $numInput / 2);
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If $numInput is even, $numInput / 2 is an integer, so int() of it has no effect. if $numInput is odd, dividing by 2 leaves something-and-a-half, , so int() of that is the int without the fraction.