28139279 has 12 divisors (see below), whose sum is σ = 32832000. Its totient is φ = 24046848.

The previous prime is 28139269. The next prime is 28139297. The reversal of 28139279 is 97293182.

It is a happy number.

It is not a de Polignac number, because 28139279 - 2²⁰ = 27090703 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 (28139249) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21362 + ... + 22640.

It is an arithmetic number, because the mean of its divisors is an integer number (2736000).

Almost surely, 2^28139279 is an apocalyptic number.

28139279 is a deficient number, since it is larger than the sum of its proper divisors (4692721).

28139279 is a wasteful number, since it uses less digits than its factorization.

28139279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1742 (or 1735 counting only the distinct ones).

The product of its digits is 54432, while the sum is 41.

The square root of 28139279 is about 5304.6469251026. The cubic root of 28139279 is about 304.1615564121.

The spelling of 28139279 in words is "twenty-eight million, one hundred thirty-nine thousand, two hundred seventy-nine".