Bluebulb Projects' The Measure of Things presents:
770,000 is about 21 times the number of Seats in Fenway Park.
In other words, it's 20.7710 times the count of Seats in Fenway Park, and the count of Seats in Fenway Park is 0.048144 times that amount.
(2013 figures; daytime capacity) (a.k.a. The Cathedral of Boston) (Boston, Massachusetts)