28179891 has 6 divisors (see below), whose sum is σ = 40704300. Its totient is φ = 18786588.

The previous prime is 28179883. The next prime is 28179901. The reversal of 28179891 is 19897182.

It is not a de Polignac number, because 28179891 - 2³ = 28179883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28179821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1565541 + ... + 1565558.

It is an arithmetic number, because the mean of its divisors is an integer number (6784050).

Almost surely, 2^28179891 is an apocalyptic number.

28179891 is a deficient number, since it is larger than the sum of its proper divisors (12524409).

28179891 is a wasteful number, since it uses less digits than its factorization.

28179891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3131105 (or 3131102 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The square root of 28179891 is about 5308.4735093999. The cubic root of 28179891 is about 304.3078130765.

The spelling of 28179891 in words is "twenty-eight million, one hundred seventy-nine thousand, eight hundred ninety-one".