my @sorted= grep {s/(^|\D)0+(\d)/$1$2/g,1} sort
    grep {s/(\d+)/sprintf"%06.6d",$1/ge,1} @data;
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Features and limitations:

• Strips extra leading zeros from digit strings
• Doesn't handle floating point numbers at all well
• Sorts negative integers in reverse after positive integers
• Uses very little extra memory
• You must specify the maximum number of digits your integers will have (6 in the above code)