28112804538 has 32 divisors (see below), whose sum is σ = 69200750976. Its totient is φ = 7414365888.

The previous prime is 28112804521. The next prime is 28112804539. The reversal of 28112804538 is 83540821182.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 28112804538.

It is not an unprimeable number, because it can be changed into a prime (28112804539) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25743781 + ... + 25744872.

It is an arithmetic number, because the mean of its divisors is an integer number (2162523468).

Almost surely, 2^28112804538 is an apocalyptic number.

28112804538 is an abundant number, since it is smaller than the sum of its proper divisors (41087946438).

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

28112804538 is a wasteful number, since it uses less digits than its factorization.

28112804538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51488678.

The product of its (nonzero) digits is 122880, while the sum is 42.

The spelling of 28112804538 in words is "twenty-eight billion, one hundred twelve million, eight hundred four thousand, five hundred thirty-eight".