On 1st April 2020, A Limited issued 2,000 - 15% Debentures of Rs.500 each at Rs.475 each to be redeemed on Ist April 2023. Debenture holders had an option to convert their holding into 15% Preference shares of Rs.100 each at a premium of Rs.25 per share. On 31st March 2021, one year's interest had accrued on these debentures and remained unpaid a holder of 100 debentures notified his intention to convert his holding into 15% Preference shares. You are required to compute the amount of securities premium and number of preference shares to be issued (without violating section 79).