28488689 has 4 divisors (see below), whose sum is σ = 28563456. Its totient is φ = 28413924.

The previous prime is 28488653. The next prime is 28488703. The reversal of 28488689 is 98688482.

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, and also an emirpimes, since its reverse is a distinct semiprime: 98688482 = 2 ⋅49344241.

It is a cyclic number.

It is not a de Polignac number, because 28488689 - 2¹² = 28484593 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28488689.

It is not an unprimeable number, because it can be changed into a prime (28488289) 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, 36809 + ... + 37574.

It is an arithmetic number, because the mean of its divisors is an integer number (7140864).

Almost surely, 2^28488689 is an apocalyptic number.

It is an amenable number.

28488689 is a deficient number, since it is larger than the sum of its proper divisors (74767).

28488689 is an equidigital number, since it uses as much as digits as its factorization.

28488689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74766.

The product of its digits is 1769472, while the sum is 53.

The square root of 28488689 is about 5337.4796486731. The cubic root of 28488689 is about 305.4153223956.

The spelling of 28488689 in words is "twenty-eight million, four hundred eighty-eight thousand, six hundred eighty-nine".