First of all, the visual magnitude
Count the sun, followed by Sirius.
Not counting the sun, the second one is the old star.
Second, absolute magnitude
Visually, Betelgeuse, -6.69, ranks behind Tianjin IV (-8.73).
However, it is hard to say whether the extremely blue massive stars such as sagittal augmentation 22 (ζ Pup) are calculated according to the true brightness. In fact, many WR stars are calculated according to absolute optical magnitude, but the ultraviolet rays of these stars are quite powerful.
Sirius and its companion stars
Type B Betelgeuse in Supergiant star and witch head nebula illuminated by it.