28521769878 has 48 divisors (see below), whose sum is σ = 71783146656. Its totient is φ = 8015483520.

The previous prime is 28521769867. The next prime is 28521769901. The reversal of 28521769878 is 87896712582.

28521769878 is a `hidden beast` number, since 28 + 521 + 7 + 6 + 9 + 87 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

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 23 ways as a sum of consecutive naturals, for example, 1847751 + ... + 1863122.

It is an arithmetic number, because the mean of its divisors is an integer number (1495482222).

Almost surely, 2^28521769878 is an apocalyptic number.

28521769878 is an abundant number, since it is smaller than the sum of its proper divisors (43261376778).

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

28521769878 is a wasteful number, since it uses less digits than its factorization.

28521769878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3710949 (or 3710946 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 63.

The spelling of 28521769878 in words is "twenty-eight billion, five hundred twenty-one million, seven hundred sixty-nine thousand, eight hundred seventy-eight".