Bb 13#11, 2nd inversion (E# in the bass)
Also written as Bb13#11/E#.
Notes, from the bass up
E# (bass)G#B#EGA#D
The same notes as Bb 13#11 (E#, G#, B#, E, G, A# and D), rearranged so E# is the lowest note. Use it to move between chords with smaller jumps across the keyboard.