28121324 has 24 divisors (see below), whose sum is σ = 61356288. Its totient is φ = 10956240.

The previous prime is 28121321. The next prime is 28121351. The reversal of 28121324 is 42312182.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 28121324.

It is not an unprimeable number, because it can be changed into a prime (28121321) 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 7 ways as a sum of consecutive naturals, for example, 45344 + ... + 45959.

It is an arithmetic number, because the mean of its divisors is an integer number (2556512).

Almost surely, 2^28121324 is an apocalyptic number.

It is an amenable number.

28121324 is an abundant number, since it is smaller than the sum of its proper divisors (33234964).

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

28121324 is a wasteful number, since it uses less digits than its factorization.

28121324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91325 (or 91323 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

The square root of 28121324 is about 5302.9542709701. The cubic root of 28121324 is about 304.0968499128.

The spelling of 28121324 in words is "twenty-eight million, one hundred twenty-one thousand, three hundred twenty-four".