Db 13b9, 5th inversion (A# in the bass)
Also written as Db13b9/A#.
Notes, from the bass up
A# (bass)C#E#G#BD
The same notes as Db 13b9 (A#, C#, E#, G#, B and D), rearranged so A# is the lowest note. Use it to move between chords with smaller jumps across the keyboard.