28139816 has 16 divisors (see below), whose sum is σ = 54464640. Its totient is φ = 13615920.

The previous prime is 28139807. The next prime is 28139819. The reversal of 28139816 is 61893182.

It is a self number, because there is not a number n which added to its sum of digits gives 28139816.

It is not an unprimeable number, because it can be changed into a prime (28139819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56486 + ... + 56981.

It is an arithmetic number, because the mean of its divisors is an integer number (3404040).

Almost surely, 2^28139816 is an apocalyptic number.

It is an amenable number.

28139816 is a deficient number, since it is larger than the sum of its proper divisors (26324824).

28139816 is a wasteful number, since it uses less digits than its factorization.

28139816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113504 (or 113500 counting only the distinct ones).

The product of its digits is 20736, while the sum is 38.

The square root of 28139816 is about 5304.6975408594. The cubic root of 28139816 is about 304.1634912368.

The spelling of 28139816 in words is "twenty-eight million, one hundred thirty-nine thousand, eight hundred sixteen".