28139828 has 24 divisors (see below), whose sum is σ = 52399872. Its totient is φ = 13176704.

The previous prime is 28139819. The next prime is 28139843. The reversal of 28139828 is 82893182.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14525 + ... + 16347.

It is an arithmetic number, because the mean of its divisors is an integer number (2183328).

Almost surely, 2^28139828 is an apocalyptic number.

It is an amenable number.

28139828 is a deficient number, since it is larger than the sum of its proper divisors (24260044).

28139828 is a wasteful number, since it uses less digits than its factorization.

28139828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2071 (or 2069 counting only the distinct ones).

The product of its digits is 55296, while the sum is 41.

The square root of 28139828 is about 5304.6986719323. The cubic root of 28139828 is about 304.1635344729.

The spelling of 28139828 in words is "twenty-eight million, one hundred thirty-nine thousand, eight hundred twenty-eight".