28559987 has 4 divisors (see below), whose sum is σ = 28719720. Its totient is φ = 28400256.

The previous prime is 28559977. The next prime is 28560019. The reversal of 28559987 is 78995582.

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 28559987 - 2¹⁶ = 28494451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28559917) 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, 79598 + ... + 79955.

It is an arithmetic number, because the mean of its divisors is an integer number (7179930).

Almost surely, 2^28559987 is an apocalyptic number.

28559987 is a deficient number, since it is larger than the sum of its proper divisors (159733).

28559987 is a wasteful number, since it uses less digits than its factorization.

28559987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159732.

The product of its digits is 1814400, while the sum is 53.

The square root of 28559987 is about 5344.1544700729. The cubic root of 28559987 is about 305.6698954905.

The spelling of 28559987 in words is "twenty-eight million, five hundred fifty-nine thousand, nine hundred eighty-seven".