A 3-multiperfect number 
. Six sous-doubles are known (120, 672, 523776, 459818240,
1476304896, and 51001180160; OEIS A005820),
and these are believed to comprise all sous-doubles.
Sous-Double
See also
Multiperfect Number, Sous-TripleExplore with Wolfram|Alpha
References
Sloane, N. J. A. Sequence A005820/M5376 in "The On-Line Encyclopedia of Integer Sequences."Referenced on Wolfram|Alpha
Sous-DoubleCite this as:
Weisstein, Eric W. "Sous-Double." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Sous-Double.html