@ragavanrajan As @v-alzhan-msft mentioned the screenshot of your configuration will help us understand your requirement better.
43873 is the number of days between 30-12-1899 to the current date, this is how format Excel stores values added to cells of 'Date' format.
To work around the problem, you will need to apply the formula below.
addDays('1899–12–30T00:00:00Z',int(item()?['YourDateColumnName']))
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