from the little I know about networking what you want is not possible: given the lonely IP address you cannot desume what the netmask value is. Infact the net can be subnetted at will resulting in a serie of a little subnets.

If you are looking to the local IP configured in some host you can retrieve how the network card is configured but it can be also misconfigured: so you cannot be sure if the mask is the rigth one.

By other hand if you know the net (not just an IP) you can retrieve useful informations using NetAddr::IP for example (warning windows double quotes!):

perl -MNetAddr::IP -e "$ip=new NetAddr::IP '189.10.136.129/27'; print 
+'net ',$ip,' mask ',$ip->mask,' first ',$ip->first,' last ',$ip->last
+"

net 189.10.136.129/27 mask 255.255.255.224 first 189.10.136.129/27 las
+t 189.10.136.158/27
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L*