Not one but two will do.

? Transform(TTOC(Datetime(),1), "@R 9999-99-99T99:99:99")

>From a datetime value, I need to obtain an XML format such as:
>
>

><CreationDate>2002-01-02T00:00:00</CreationDate>
>

>
>Is there any builtin function that will allow me to obtain that or I need to parse it manually?