28381885 has 16 divisors (see below), whose sum is σ = 40617216. Its totient is φ = 18615168.

The previous prime is 28381883. The next prime is 28381907. The reversal of 28381885 is 58818382.

It is a cyclic number.

It is not a de Polignac number, because 28381885 - 2¹ = 28381883 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28381883) 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 15 ways as a sum of consecutive naturals, for example, 16824 + ... + 18433.

It is an arithmetic number, because the mean of its divisors is an integer number (2538576).

Almost surely, 2^28381885 is an apocalyptic number.

It is an amenable number.

28381885 is a deficient number, since it is larger than the sum of its proper divisors (12235331).

28381885 is a wasteful number, since it uses less digits than its factorization.

28381885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35292.

The product of its digits is 122880, while the sum is 43.

The square root of 28381885 is about 5327.4651570893. The cubic root of 28381885 is about 305.0331774354.

The spelling of 28381885 in words is "twenty-eight million, three hundred eighty-one thousand, eight hundred eighty-five".