28905189 has 8 divisors (see below), whose sum is σ = 38818080. Its totient is φ = 19131216.

The previous prime is 28905187. The next prime is 28905203. The reversal of 28905189 is 98150982.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28905189 - 2¹ = 28905187 is a prime.

It is a super-2 number, since 2×28905189² = 1671019902251442, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 28905189.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28905187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34242 + ... + 35075.

It is an arithmetic number, because the mean of its divisors is an integer number (4852260).

Almost surely, 2^28905189 is an apocalyptic number.

It is an amenable number.

28905189 is a deficient number, since it is larger than the sum of its proper divisors (9912891).

28905189 is a wasteful number, since it uses less digits than its factorization.

28905189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69459.

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 28905189 is about 5376.3546200004. The cubic root of 28905189 is about 306.8965015913.

The spelling of 28905189 in words is "twenty-eight million, nine hundred five thousand, one hundred eighty-nine".