28939879 has 4 divisors (see below), whose sum is σ = 28953040. Its totient is φ = 28926720.

The previous prime is 28939877. The next prime is 28939949. The reversal of 28939879 is 97893982.

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 28939879 - 2¹ = 28939877 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 (28939877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2394 + ... + 7975.

It is an arithmetic number, because the mean of its divisors is an integer number (7238260).

Almost surely, 2^28939879 is an apocalyptic number.

28939879 is a deficient number, since it is larger than the sum of its proper divisors (13161).

28939879 is a wasteful number, since it uses less digits than its factorization.

28939879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13160.

The product of its digits is 1959552, while the sum is 55.

The square root of 28939879 is about 5379.5798163054. The cubic root of 28939879 is about 307.0192244643.

The spelling of 28939879 in words is "twenty-eight million, nine hundred thirty-nine thousand, eight hundred seventy-nine".