28788569 has 4 divisors (see below), whose sum is σ = 28869120. Its totient is φ = 28708020.

The previous prime is 28788559. The next prime is 28788577. The reversal of 28788569 is 96588782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28788569 - 2⁸ = 28788313 is a prime.

It is a super-2 number, since 2×28788569² = 1657563410135522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 28788569.

It is not an unprimeable number, because it can be changed into a prime (28788559) 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, 39737 + ... + 40454.

It is an arithmetic number, because the mean of its divisors is an integer number (7217280).

Almost surely, 2^28788569 is an apocalyptic number.

It is an amenable number.

28788569 is a deficient number, since it is larger than the sum of its proper divisors (80551).

28788569 is an equidigital number, since it uses as much as digits as its factorization.

28788569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80550.

The product of its digits is 1935360, while the sum is 53.

The square root of 28788569 is about 5365.4980197555. The cubic root of 28788569 is about 306.4832135023.

The spelling of 28788569 in words is "twenty-eight million, seven hundred eighty-eight thousand, five hundred sixty-nine".