Re: How do I print a large integer with thousands separators?

[hanspoo]

$num = 123456789;
$num = reverse $num;     # reverse the number's digits
$num =~ s/(\d{3})/$1,/g; # insert comma every 3 digits, from beginning
$num = reverse $num;     # Reverse the result
$num =~ s/^\,//;         # remove leading comma, if any

[stevecomrie]

For other more indepth formatting, there's always Number::Format