I find it hard to parse large numbers unless they have thousands-separators. It turns out that it's much easier to add separators than the docs make it appear: one environment var in your console's config file, and an option to the long-form list command (which is the only version of the list command with which it works).
[I use tcsh as my console, so if you don't, you'll need to make appropriate changes.]
# This environment var is all that's needed to identify the separator.
# The language and charset should reflect your location and preference, of course
# I aliased in more options, but the comma option is what triggers the separator's display
# regardless of what the conventional separator char is for your locale
[I use tcsh as my console, so if you don't, you'll need to make appropriate changes.]
# This environment var is all that's needed to identify the separator.
# The language and charset should reflect your location and preference, of course
setenv LC_NUMERIC "en_US.UTF-8" # I aliased in more options, but the comma option is what triggers the separator's display
# regardless of what the conventional separator char is for your locale
alias ls 'ls -, -FAl'