Sorry for replying in English, I don't speak Portuguese.
When I completed my CMNA I received an e-mail with a link to an image that could be used in my e-mail signature:
"Having completed the training, you can now use the CMNA logo in your email signature to indicate your status as a Certified Meraki Networking Associate. You can also download your PDF certificate on the CMNA page at merakipartners.com (Partner participants) and merakitools.com (Cisco participants) by selecting the "Download your CMNA Certificate here" link at the top of the page."
"CMNA logo" was a hyperlink to that image.
Afaik CMNA doesn't have a number associated to it like CCIE does (at least I don't see it anywhere). For my CMNO I do have a number.