28131572865 has 16 divisors (see below), whose sum is σ = 49102382016. Its totient is φ = 13639550400.

The previous prime is 28131572863. The next prime is 28131572869. The reversal of 28131572865 is 56827513182.

It is not a de Polignac number, because 28131572865 - 2¹ = 28131572863 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28131572863) 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, 85247026 + ... + 85247355.

It is an arithmetic number, because the mean of its divisors is an integer number (3068898876).

Almost surely, 2^28131572865 is an apocalyptic number.

It is an amenable number.

28131572865 is a deficient number, since it is larger than the sum of its proper divisors (20970809151).

28131572865 is a wasteful number, since it uses less digits than its factorization.

28131572865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170494400.

The product of its digits is 806400, while the sum is 48.

The spelling of 28131572865 in words is "twenty-eight billion, one hundred thirty-one million, five hundred seventy-two thousand, eight hundred sixty-five".