That is a Danish bicycle identification number. It was imported by a company called Egedeso who marketed under the Everton brand. The date code could represent a number of different years but based on the frame features it should be 1990. It looks like a very basic frame for the period, yet it has what appears to be a number plate boss under the top tube, just behind the head lug.

Cykler - Everton - damecykler, herrecykler, børnecykler, mountainbikes, retro, city, MTB