Custom Format Cell Excel 2019

[public]

I have been trying for some time to format an excel cell so that it displays the following:

xxxx/ dd.mm.yyyy

where "xxx" can be any integer: 0...9999.

So, when I type 012304052020, then the cell will display: 0123/ 04.05.2020

How can I do that?

[hrlngrv]

You can't enter BOTH a number AND a date in the same cell with one interpreted as a number and the other interpreted as a date.

You could enter 12-digit numbers which display as you want using the custom number format 0000\/ 00\.00\.0000, but 12-digit numbers formatted that way would be treated as single numbers, so 012304052020 displayed as 0123/ 04.05.2020 would be equal to the number 12,304,052,020.