When Task sends the output of completed data, it uses the Unix timestamp format. "Unix time is a single signed number which increments every second, without requiring the calculations to determine year, month, day of month, hour and minute required for intelligibility to humans."
In the output Task sends to Zapier you should see "Meta Data Timestamp" - that's your Unix timestamp and is what you'll use to convert:
Zapier have created a how to here:
You will be adding a step to your Zap before you send your Task data into whatever application you have chosen.