28078781886 has 24 divisors (see below), whose sum is σ = 60842769624. Its totient is φ = 9358761840.

The previous prime is 28078781849. The next prime is 28078781897. The reversal of 28078781886 is 68818787082.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 159076 + ... + 285416.

It is an arithmetic number, because the mean of its divisors is an integer number (2535115401).

Almost surely, 2^28078781886 is an apocalyptic number.

28078781886 is an abundant number, since it is smaller than the sum of its proper divisors (32763987738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28078781886 is a wasteful number, since it uses less digits than its factorization.

28078781886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138696 (or 138693 counting only the distinct ones).

The product of its (nonzero) digits is 19267584, while the sum is 63.

The spelling of 28078781886 in words is "twenty-eight billion, seventy-eight million, seven hundred eighty-one thousand, eight hundred eighty-six".