28231391028 has 24 divisors (see below), whose sum is σ = 65879876160. Its totient is φ = 9409516480.

The previous prime is 28231390991. The next prime is 28231391039. The reversal of 28231391028 is 82019313282.

It is a super-2 number, since 2×28231391028² (a number of 22 digits) contains 22 as substring.

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, 11488 + ... + 237896.

It is an arithmetic number, because the mean of its divisors is an integer number (2744994840).

Almost surely, 2^28231391028 is an apocalyptic number.

It is an amenable number.

28231391028 is an abundant number, since it is smaller than the sum of its proper divisors (37648485132).

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

28231391028 is a wasteful number, since it uses less digits than its factorization.

28231391028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236807 (or 236805 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The spelling of 28231391028 in words is "twenty-eight billion, two hundred thirty-one million, three hundred ninety-one thousand, twenty-eight".