As many as 13 companies have fixed Wednesday as the record date for their dividend payouts, effectively making today the last day for interested investors to buy these stocks to be eligible for the payouts.Under Sebi's T+1 settlement cycle, investors need to purchase a company's shares at least one trading day before the record date to ensure the shares are credited to their demat accounts in time, and they become eligible for the corporate action. Accordingly, today is the last opportunity for investors to buy the shares so that they are credited to their accounts by the record date (September…