how to find the number of members in a Windows IP multicast

Question

I am able to find multicast groups by using this in Command Prompt (I found this at serverfault How do I know if IP Multicasting is enabled on my network in Windows?).

netsh interface ip show joins

Here is the result:

Scope       References  Last  Address
----------  ----------  ----  ---------------------------------
0                    0  Yes   213.0.0.1
0                    1  Yes   213.0.0.23

I am able to use 213.0.0.23 for the multicast IP address to send/receive data. My question is how I can find the number of members in a multicast group?

Thanks!