those are huge numbers, first of all if Russia was to engage so many soldiers....
The vast majority of those "soldiers" would be support personnel not involved in actual fighting. And while there is no doubt that Russia could over run Ukraine in a matter of days if that's what they wanted, clearly that's NOT what they want. They are, for now, content in simply taking the Eastern portion of Ukraine. And the recent accidentally revealed data shows they are suffering serious casualties while doing that. And the government is using extraordinary (but so far effective) measures to hide that fact from its own citizens.