I have a macbook on Mojave MacOS. It had an older version of Teamviewer installed. I uninstalled that through the Teamviewer app and checked the "remove all settings data." When I download either version of Teamviewer, plain Teamviewer or Teamviewer Host, whether it's on that macbook or from another macbook running Big Sur, it still appears to be 32-bit Teamviewer on the Mojave macbook. I want to have 64-bit Teamviewer on the Mojave macbook before I upgrade it to Big Sur.
I'm using the About this Mac, System Report, Software, Legacy Software. Teamviewer is still listed on there. From what I understand those are 32-bit apps and will cause problems if the machine is upgraded to Big Sur.
I found this page, saying Macs only have 64-bit Teamviewer. So maybe it's just the About this Mac page being off? Or maybe Teamviewer doesn't completely uninstall and some 32-bit settings are still there?