28664329 has 4 divisors (see below), whose sum is σ = 30350484. Its totient is φ = 26978176.

The previous prime is 28664309. The next prime is 28664341. The reversal of 28664329 is 92346682.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15327225 + 13337104 = 3915^2 + 3652^2 .

It is a cyclic number.

It is not a de Polignac number, because 28664329 - 2⁷ = 28664201 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28664291 and 28664300.

It is not an unprimeable number, because it can be changed into a prime (28664309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 843052 + ... + 843085.

It is an arithmetic number, because the mean of its divisors is an integer number (7587621).

Almost surely, 2^28664329 is an apocalyptic number.

It is an amenable number.

28664329 is a deficient number, since it is larger than the sum of its proper divisors (1686155).

28664329 is a wasteful number, since it uses less digits than its factorization.

28664329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1686154.

The product of its digits is 124416, while the sum is 40.

The square root of 28664329 is about 5353.9078251311. The cubic root of 28664329 is about 306.0416912452.

The spelling of 28664329 in words is "twenty-eight million, six hundred sixty-four thousand, three hundred twenty-nine".