28149689 has 4 divisors (see below), whose sum is σ = 28165200. Its totient is φ = 28134180.

The previous prime is 28149683. The next prime is 28149701. The reversal of 28149689 is 98694182.

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: 98694182 = 2 ⋅49347091.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28149689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28149683) 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, 4607 + ... + 8804.

It is an arithmetic number, because the mean of its divisors is an integer number (7041300).

Almost surely, 2^28149689 is an apocalyptic number.

It is an amenable number.

28149689 is a deficient number, since it is larger than the sum of its proper divisors (15511).

28149689 is a wasteful number, since it uses less digits than its factorization.

28149689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15510.

The product of its digits is 248832, while the sum is 47.

The square root of 28149689 is about 5305.6280495338. The cubic root of 28149689 is about 304.1990595221.

The spelling of 28149689 in words is "twenty-eight million, one hundred forty-nine thousand, six hundred eighty-nine".