28638844 has 24 divisors (see below), whose sum is σ = 54740448. Its totient is φ = 13030080.

The previous prime is 28638821. The next prime is 28638847. The reversal of 28638844 is 44883682.

It is a self number, because there is not a number n which added to its sum of digits gives 28638844.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28638847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187 + ... + 7570.

It is an arithmetic number, because the mean of its divisors is an integer number (2280852).

Almost surely, 2^28638844 is an apocalyptic number.

It is an amenable number.

28638844 is a deficient number, since it is larger than the sum of its proper divisors (26101604).

28638844 is a wasteful number, since it uses less digits than its factorization.

28638844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7845 (or 7843 counting only the distinct ones).

The product of its digits is 294912, while the sum is 43.

The square root of 28638844 is about 5351.5272586431. The cubic root of 28638844 is about 305.9509654153.

The spelling of 28638844 in words is "twenty-eight million, six hundred thirty-eight thousand, eight hundred forty-four".