How can I make a call to an SIP address from Google Voice number? How can I make a call to an SIP address (e.g. sip:613@fwd.pulver.com) from Google Voice number?
Does Google Hangout support calls to SIP addresses?

Can an SIP address call my Google Voice number? 

Thanks.
The answer is no. Google voice is no longer accepting SIP traffic. See here for more info.