Write recursive t-sql code to get Square root of integer number without using SQRT function

Create Function [dbo].[fn_SQRT](@v_Number bigint,@v_ID bigint)
Returns bigint
as
Begin
If (@v_Number != 1)
Begin
if (@v_Number%@v_ID = 0)
Begin
Set @v_Number = @v_Number/(@v_ID * @v_ID)

return @v_ID * dbo.fn_SQRT(@v_Number, @v_ID)
End
Else
Begin
return dbo.fn_SQRT(@v_Number, @v_ID + 1)
End
End
return 1
End
GO

select [dbo].[fn_SQRT](63297936, 2)
Go

--> 7956