28728324 has 24 divisors (see below), whose sum is σ = 74481120. Its totient is φ = 9576072.

The previous prime is 28728319. The next prime is 28728341. The reversal of 28728324 is 42382782.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 132894 + ... + 133109.

It is an arithmetic number, because the mean of its divisors is an integer number (3103380).

Almost surely, 2^28728324 is an apocalyptic number.

It is an amenable number.

28728324 is an abundant number, since it is smaller than the sum of its proper divisors (45752796).

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

28728324 is a wasteful number, since it uses less digits than its factorization.

28728324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266016 (or 266008 counting only the distinct ones).

The product of its digits is 43008, while the sum is 36.

The square root of 28728324 is about 5359.8809688276. The cubic root of 28728324 is about 306.2692746997.

The spelling of 28728324 in words is "twenty-eight million, seven hundred twenty-eight thousand, three hundred twenty-four".