What is the last digit of the sum S = 9²⁷ + 27⁹ ?

What is the sum of all the divisors of 256?

What is the LCM of 3·6, 0·009, 0·27?

The value of a 2-digit number is 5 times the sum of the digits. What is the product of the digits ?

What is the digit at the 100th place of number (225)⁴⁰ ?

Unit digit of 1³+2³+3³+...+9³ is