Regarding ASASSN-15lh, how bright was it estimated to be compared to the Milky Way galaxy at its peak?

Answer

About 50 times brighter than the entire Milky Way galaxy.

The record-breaking supernova ASASSN-15lh was estimated to have a peak luminosity fifty times greater than the collective light of the Milky Way galaxy.

Regarding ASASSN-15lh, how bright was it estimated to be compared to the Milky Way galaxy at its peak?
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