28728442 has 16 divisors (see below), whose sum is σ = 43719912. Its totient is φ = 14156800.

The previous prime is 28728383. The next prime is 28728443. The reversal of 28728442 is 24482782.

It can be written as a sum of positive squares in 4 ways, for example, as 18224361 + 10504081 = 4269^2 + 3241^2 .

It is not an unprimeable number, because it can be changed into a prime (28728443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71442 + ... + 71842.

Almost surely, 2^28728442 is an apocalyptic number.

28728442 is a deficient number, since it is larger than the sum of its proper divisors (14991470).

28728442 is a wasteful number, since it uses less digits than its factorization.

28728442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833.

The product of its digits is 57344, while the sum is 37.

The square root of 28728442 is about 5359.8919765234. The cubic root of 28728442 is about 306.2696940271.

The spelling of 28728442 in words is "twenty-eight million, seven hundred twenty-eight thousand, four hundred forty-two".