28578089 has 4 divisors (see below), whose sum is σ = 28726356. Its totient is φ = 28429824.

The previous prime is 28578083. The next prime is 28578091. The reversal of 28578089 is 98087582.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98087582 = 2 ⋅49043791.

It can be written as a sum of positive squares in 2 ways, for example, as 4243600 + 24334489 = 2060^2 + 4933^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28578089 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28578083) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73844 + ... + 74229.

It is an arithmetic number, because the mean of its divisors is an integer number (7181589).

Almost surely, 2^28578089 is an apocalyptic number.

It is an amenable number.

28578089 is a deficient number, since it is larger than the sum of its proper divisors (148267).

28578089 is a wasteful number, since it uses less digits than its factorization.

28578089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148266.

The product of its (nonzero) digits is 322560, while the sum is 47.

The square root of 28578089 is about 5345.8478279876. The cubic root of 28578089 is about 305.7344621378.

The spelling of 28578089 in words is "twenty-eight million, five hundred seventy-eight thousand, eighty-nine".