In preparation for the final coup at the Kopenhagen opera house, Egon orders that they obtain 16 explosive charges. During the actual coup, however, there are 24 explosions.
When Keld and Benny knocks down the wall in the cellar, all the bricks disappear when they run towards Egon.
The Chinese vase that is stolen by the gang is said to be more than 1,000 years old, made in the first Ming period. However, the Ming period began in 1368, which is only around 600 years before the movie.
The first time Egon mentions the value of the fake vase, it is Dkr. 14.75. The next time he mentions it, it is Dkr. 14.85.
There was no need to put Egon Olsen in danger by placing him inside the cooker. He could have entered the scene in their car, disguised or hidden.