You can find this detail browsing below link..
http://www.cisco.com/c/en/us/td/docs/routers/access/vg350/hardware/installation/guide/vg350_hig/vg350higovw.pdf
http://www.cisco.com/c/en/us/products/collateral/unified-communications/vg-series-gateways/product_data_sheet09186a00801d87f6.html
Maximum ports: 160
Suresh