There are 69806980 lockers numbered inorder from 1 to 69806980 along a hall. At any given point, each lockeris in one of two possible states---either its door isopenor its door isclosed. To begin with, all of thelocker doors are closed. You are given the following step by stepinstructions:

1. Change the state of all of the lockers.
2. Change the state of every second locker.
3. Change the state of every third locker.

Change the state of the last locker.

What is the largest locker that will be open after this is done?