\d matches a digit. There are more digits than 0,1,2,3,4,5,6,7,8,9.

$ perl -Mcharnames=:full -le'print "\N{BENGALI DIGIT ZERO}" =~ /^\d\z/
+ || 0'
1
[download]

The same thing, written differently:

$ perl -le'print chr(0x09E6) =~ /^\d\z/ || 0'
1
[download]