Which followers are a different level than the Dragonborn?

Solution 1:

When I checked, the Elder Scrolls Wiki did not list a multiplier for every follower, but UESP did.

There are three followers with multipliers less than 1, and two with multipliers over 1:

Roggi Knot-Beard: PC×0.75 (range=6-20)
Sven: PC×0.75 (range=6-20)
Adelaisa Vendicci: PC×0.9 (range=6-25)

Mjoll the Lioness: PC×1.25 (range=10-40)
Erandur: PC×1.5 (range=6-50)

This explains why Erandur is so awesome, as anyone who has used him has probably noticed.

Most animal followers and a few people have set levels that do not change. Talvas Fathryon, for instance, is always level 25.