28780589 has 4 divisors (see below), whose sum is σ = 28831740. Its totient is φ = 28729440.

The previous prime is 28780571. The next prime is 28780607. The reversal of 28780589 is 98508782.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98508782 = 2 ⋅49254391.

It is an interprime number because it is at equal distance from previous prime (28780571) and next prime (28780607).

It can be written as a sum of positive squares in 2 ways, for example, as 11847364 + 16933225 = 3442^2 + 4115^2 .

It is a cyclic number.

It is not a de Polignac number, because 28780589 - 2²⁰ = 27732013 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 (28780519) 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 3 ways as a sum of consecutive naturals, for example, 24722 + ... + 25859.

It is an arithmetic number, because the mean of its divisors is an integer number (7207935).

Almost surely, 2^28780589 is an apocalyptic number.

It is an amenable number.

28780589 is a deficient number, since it is larger than the sum of its proper divisors (51151).

28780589 is an equidigital number, since it uses as much as digits as its factorization.

28780589 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51150.

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

The square root of 28780589 is about 5364.7543280191. The cubic root of 28780589 is about 306.4548925153.

The spelling of 28780589 in words is "twenty-eight million, seven hundred eighty thousand, five hundred eighty-nine".