Mahoraga destroys a chunk of a building (JJK)

https://www.reddit.com/r/FeatCalcing/s/JeyI6Pp4Rm

It's either rectangular or cube so let's begin

Rectangular

392.6 cm times 410.4 cm times 14.4 cm Minus 87% hollowness

301622.3314 cm3

Times 6 J/CC

1809733.9884J

Now cube

It's Length is 170 cm on the other side

4913000 cm3

Minus 87%

638690 cm3

Times 6 J/CC

3832140J