Given that it does not report 33 as rotatable I don't see your point. Also the digits 347 are not stripped, they are replaced with the digit 6, see the man for tr. It would not actually matter if they were stripped or replaced the original value will not be equal to the reversed value. 

sub is_rotatable{
#234567890123456789012345678901234567
$_=$_[0];y/2569347/5296/;pop==reverse
}

for my $i(3,33,131,141,171,25696925,101,88) {
    printf "%s %s rotatable\n", $i, is_rotatable( $i ) ? 'is' : 'not'
}

__DATA__
3 not rotatable
33 not rotatable
131 not rotatable
141 not rotatable
171 not rotatable
25696925 is rotatable
101 is rotatable
88 is rotatable

[download]

cheers

tachyon

In reply to Re^3: (Challenge) Rotateable numbers by tachyon
in thread (Challenge) Rotateable numbers by FoxtrotUniform

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