If there is no mention of 64-bit in the About IE screen, the 32-bit version is opening.
You can check the shortcuts you use to open IE.
Right-click the shortcut> Properties. The Target for 32-bit IE will be
["C:\Program Files (x86)\Internet Explorer\iexplore.exe"] the 64-bit would be
["C:\Program Files\Internet Explorer\iexplore.exe"]