March 2, 2014 in answer
The result shown by
sudo lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL performs calculations using the binary prefix i.e. multiples of 1024 (which is 210). So 500107862016 bytes would be equal to 465.76 GB or approximately 466 GB. (You can use
-b switch to print in bytes instead of human readable as
sudo lsblk -b -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL.)
Calculation: 500107862016 bytes = (500107862016 / (1024 ^ 3)) GB = 465.76 GB
While Disks Utility uses decimal prefix for calculation so expressed as multiples of 1000. So 500107862016 bytes here would mean 500.11 GB or 500 GB approx.
Calculation: 500107862016 bytes = (500107862016 / (1000 ^ 3)) GB = 500.11 GB