mh, ok, repeat after me *grin*:
ALL INTEGERS BIGGER THAN 0 ARE NATURAL NUMBERS !

Have a nice day
All decision is left to your taste
Update:
Uhm ok, seems I got you wrong here.
so did you mean the solution would more look alike

$ perl -e '$sum += length($_) for ( 1..1000000 );print $sum'
[download]

But then I ask myself if that question is not much more tricky, cause there are only 10 decimal numbers we use to represent all numbers. So what is teh right answer though?
the result of the above, as it is 5888896 or simply 10?