28561432564 has 24 divisors (see below), whose sum is σ = 57132410048. Its totient is φ = 12238568640.

The previous prime is 28561432553. The next prime is 28561432631. The reversal of 28561432564 is 46523416582.

It is a happy number.

It is a super-2 number, since 2×28561432564² (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, 91792 + ... + 256024.

Almost surely, 2^28561432564 is an apocalyptic number.

It is an amenable number.

28561432564 is an abundant number, since it is smaller than the sum of its proper divisors (28570977484).

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

28561432564 is a wasteful number, since it uses less digits than its factorization.

28561432564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170455 (or 170453 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 46.

The spelling of 28561432564 in words is "twenty-eight billion, five hundred sixty-one million, four hundred thirty-two thousand, five hundred sixty-four".