28578621 has 16 divisors (see below), whose sum is σ = 39477248. Its totient is φ = 18370800.

The previous prime is 28578587. The next prime is 28578623. The reversal of 28578621 is 12687582.

It is not a de Polignac number, because 28578621 - 2¹⁹ = 28054333 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28578621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28578623) 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 15 ways as a sum of consecutive naturals, for example, 44976 + ... + 45606.

It is an arithmetic number, because the mean of its divisors is an integer number (2467328).

Almost surely, 2^28578621 is an apocalyptic number.

It is an amenable number.

28578621 is a deficient number, since it is larger than the sum of its proper divisors (10898627).

28578621 is a wasteful number, since it uses less digits than its factorization.

28578621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1152.

The product of its digits is 53760, while the sum is 39.

The square root of 28578621 is about 5345.8975859999. The cubic root of 28578621 is about 305.7363592757.

The spelling of 28578621 in words is "twenty-eight million, five hundred seventy-eight thousand, six hundred twenty-one".