Transform int(64) field into a readable date

[giovanni.chiozza_1]

Hello,

I'm trying to convert a MongoDb date (int 64) into a readable date .
As you can see below I'm trying to use filter expression mini script but I'm not a programmer and probably I'm wronging something.
Is there someone who can help me on this matter ?
Thanks 

As sample I took creationDate field but there are many with same issue.

[mahadiosb]

If you get date data in int64 then you can convert it like below:

[giovanni.chiozza_1]

Thanks so much !! I'll try asap