Serial date to calendar date time in a custom format

I need help in converting a serial date time (input as string or double) to a calendar date time in the following custom format yyyy-mm-ddThh:mmZ.

I tried DateTimeAdd function but it just doesn’t pick up the actual hours and minutes.

I also tried the date time tool but having trouble with string / date time fields.

thanks

Accepted answers

This will do it

Can you post samples of your input data and desired output format.

the input is 43735.5919097222 (double or string)

the output: 2019-09-27T14:12Z

thanks heaps