28380871 has 4 divisors (see below), whose sum is σ = 30050352. Its totient is φ = 26711392.

The previous prime is 28380857. The next prime is 28380893. The reversal of 28380871 is 17808382.

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

It is a cyclic number.

It is not a de Polignac number, because 28380871 - 2⁷ = 28380743 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28380871.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28380571) 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, 834715 + ... + 834748.

It is an arithmetic number, because the mean of its divisors is an integer number (7512588).

Almost surely, 2^28380871 is an apocalyptic number.

28380871 is a deficient number, since it is larger than the sum of its proper divisors (1669481).

28380871 is a wasteful number, since it uses less digits than its factorization.

28380871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669480.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 28380871 is about 5327.3699890284. The cubic root of 28380871 is about 305.0295447506.

The spelling of 28380871 in words is "twenty-eight million, three hundred eighty thousand, eight hundred seventy-one".