Bluebulb Projects' The Measure of Things presents:
5,100 is about two-and-a-half times the number of Steps in the Sears Tower.
In other words, it's 2.4180 times the count of Steps in the Sears Tower, and the count of Steps in the Sears Tower is 0.41360 times that amount.
(a.k.a. Willis Tower) (Chicago, Illinois) (steps per stairwell)