28821879 has 24 divisors (see below), whose sum is σ = 45079920. Its totient is φ = 18197136.

The previous prime is 28821869. The next prime is 28821883. The reversal of 28821879 is 97812882.

It is a happy number.

It is not a de Polignac number, because 28821879 - 2⁹ = 28821367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28821869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8269 + ... + 11225.

It is an arithmetic number, because the mean of its divisors is an integer number (1878330).

Almost surely, 2^28821879 is an apocalyptic number.

28821879 is a deficient number, since it is larger than the sum of its proper divisors (16258041).

28821879 is a wasteful number, since it uses less digits than its factorization.

28821879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3004 (or 2979 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The square root of 28821879 is about 5368.6012144692. The cubic root of 28821879 is about 306.6013740695.

It can be divided in two parts, 2882 and 1879, that added together give a square (4761 = 69²).

The spelling of 28821879 in words is "twenty-eight million, eight hundred twenty-one thousand, eight hundred seventy-nine".