C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number 'Inf'"
20
C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number 'foo'"
0
C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number 'inf'"
20
C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number '7'"
1
C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number '7874321907'"
2
C:\>perl -e "use Scalar::Util(looks_like_number); print looks_like_number(7874321907)"
8704