121312928 has 24 divisors (see below), whose sum is σ = 260547840. Its totient is φ = 55142080.

The previous prime is 121312927. The next prime is 121312937. The reversal of 121312928 is 829213121.

It is a self number, because there is not a number n which added to its sum of digits gives 121312928.

It is not an unprimeable number, because it can be changed into a prime (121312927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171968 + ... + 172671.

It is an arithmetic number, because the mean of its divisors is an integer number (10856160).

Almost surely, 2^121312928 is an apocalyptic number.

It is an amenable number.

121312928 is an abundant number, since it is smaller than the sum of its proper divisors (139234912).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121312928 is a wasteful number, since it uses less digits than its factorization.

121312928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344660 (or 344652 counting only the distinct ones).

The product of its digits is 1728, while the sum is 29.

The square root of 121312928 is about 11014.2148154101. The cubic root of 121312928 is about 495.0347599982.

It can be divided in two parts, 1213 and 12928, that added together give a palindrome (14141).

The spelling of 121312928 in words is "one hundred twenty-one million, three hundred twelve thousand, nine hundred twenty-eight".