What is the PS Vita’s Internet Browser ‘User Agent’?

The PS Vita’s Internet Browser can be identified as:
Mozilla/5.0 (Playstation Vita x.xx) AppleWebKit/531.22.8 (KHTML, like Gecko) Silk/3.2

For example, if you are running Firmware 1.61, your PS Vita user agent will look like:
Mozilla/5.0 (Playstation Vita 1.61) AppleWebKit/531.22.8 (KHTML, like Gecko) Silk/3.2