Google Calculator

Enter following expressions to the Google search or Google calculator and find out answers.
01. "the loneliest number"
02. "once in a blue moon"
03. "Answer to life the universe and everything"  -will give an answer related to the story hitchhiker's guide to the galaxy
04. "399,999,999,999,999-399,999,999,999,998"   - Google is wrong.  :O