28806559 has 4 divisors (see below), whose sum is σ = 29509200. Its totient is φ = 28103920.

The previous prime is 28806553. The next prime is 28806563. The reversal of 28806559 is 95560882.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28806559 - 2¹⁷ = 28675487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28806553) 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 3 ways as a sum of consecutive naturals, for example, 351259 + ... + 351340.

It is an arithmetic number, because the mean of its divisors is an integer number (7377300).

Almost surely, 2^28806559 is an apocalyptic number.

28806559 is a deficient number, since it is larger than the sum of its proper divisors (702641).

28806559 is an equidigital number, since it uses as much as digits as its factorization.

28806559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702640.

The product of its (nonzero) digits is 172800, while the sum is 43.

The square root of 28806559 is about 5367.1742099544. The cubic root of 28806559 is about 306.5470407447.

The spelling of 28806559 in words is "twenty-eight million, eight hundred six thousand, five hundred fifty-nine".