SQL error - Arithmetic overflow error converting expression to data type int.

Hello,
I am trying to get result from simple equations as below:
Select 508828125*5
Select 98000 * 805545
But surprisingly not been able to get the result. Error showing is: 
Arithmetic overflow error converting expression to data type int.
I tried with bigger values also... but getting the proper result.

Please do help me out.

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