If you follow the 4% rule you'd start out taking $160k/year plus whatever you think you'll get from SS, so you'd probably be over $200k a year. Following the 4% rule would allow you to keep up with inflation (in theory)

I think most people could be comfortable with that depending on what expenses you have but you won't necessarily be living large off just $200k/year, though $4 million sounds like a lot.