Not sure what you mean by "number formatted date"? Do you mean the DATEVALUE function in Excel?
This is not the same thing - but you could find out the number of seconds since a certain starting time, and use that number.
In this example Formula Numeric - the "start" is 1/1/1970, and the "end" is the current time, and the it returns the # of seconds.
You can change the StartDateTime and EndDateTime variables in the first two lines to adjust the dates.
var DateTime EndDateTime = Now();
var DateTime StartDateTime = ToTimestamp(Date(1970, 1, 1));
var Number NumSeconds = ToSeconds( $EndDateTime - $StartDateTime );
$NumSeconds
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