For numbers upto 2**53 (~16 decimal digits), you could use this: 

sub hexFromI53{
    my $n = shift;
    my $lo = $n % ( 2**32 );
    my $hi = int( $n / 2**32 );
    return sprintf "%x%08x", $hi, $lo;
};;

print hexFromI53( 24600988483 );;
5ba554b43

print hexFromI53( 9_007_199_254_740_992 );;
20000000000000

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In reply to Re: String to Hex by BrowserUk
in thread String to Hex by augustpete

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