28890769 has 4 divisors (see below), whose sum is σ = 30590244. Its totient is φ = 27191296.

The previous prime is 28890761. The next prime is 28890781. The reversal of 28890769 is 96709882.

It is a happy number.

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 22439169 + 6451600 = 4737^2 + 2540^2 .

It is not a de Polignac number, because 28890769 - 2³ = 28890761 is a prime.

It is a super-2 number, since 2×28890769² = 1669353066822722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (49) 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 not an unprimeable number, because it can be changed into a prime (28890761) 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, 849712 + ... + 849745.

It is an arithmetic number, because the mean of its divisors is an integer number (7647561).

Almost surely, 2^28890769 is an apocalyptic number.

It is an amenable number.

28890769 is a deficient number, since it is larger than the sum of its proper divisors (1699475).

28890769 is a wasteful number, since it uses less digits than its factorization.

28890769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1699474.

The product of its (nonzero) digits is 435456, while the sum is 49.

The square root of 28890769 is about 5375.0133953321. The cubic root of 28890769 is about 306.8454590412.

The spelling of 28890769 in words is "twenty-eight million, eight hundred ninety thousand, seven hundred sixty-nine".