I see similar numbers:

angel@lucifer:~$ sysctl hw | grep mem
hw.physmem=8453619712
hw.usermem=8453464064
angel@lucifer:~$ top | grep Memory
Memory: Real: 98M/4030M act/tot Free: 3779M Cache: 3116M Swap: 0K/4088K

I always took for granted that top output was to be interpreted as 'Real:' + 'Free:' = total memory, but now I'm deep in a sea of doubt 😕

CC: @Hetzner_Online@social.cologne