28531517988 has 48 divisors (see below), whose sum is σ = 68739485696. Its totient is φ = 9201250080.

The previous prime is 28531517981. The next prime is 28531518023. The reversal of 28531517988 is 88971513582.

It is not an unprimeable number, because it can be changed into a prime (28531517981) 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, 1816095 + ... + 1831737.

Almost surely, 2^28531517988 is an apocalyptic number.

It is an amenable number.

28531517988 is an abundant number, since it is smaller than the sum of its proper divisors (40207967708).

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

28531517988 is a wasteful number, since it uses less digits than its factorization.

28531517988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20584 (or 20582 counting only the distinct ones).

The product of its digits is 4838400, while the sum is 57.

It can be divided in two parts, 285315 and 17988, that added together give a palindrome (303303).

The spelling of 28531517988 in words is "twenty-eight billion, five hundred thirty-one million, five hundred seventeen thousand, nine hundred eighty-eight".