The default alignment of numbers in a cell is:

In Microsoft Excel, the default alignment for different types of data depends on the data type. For numbers, the default alignment is to the right side of the cell. This means when you enter a numeric value—like 100, 5.75, or -42—it will automatically align along the right edge of the cell unless you change the alignment manually.

On the other hand:

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  Text values align by default to the Left.

  
  


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  Dates and time values (which are also treated as numbers internally) also align to the Right.

  
  


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  Center and Justified are manual alignment options, not defaults.