81533117528 has 32 divisors (see below), whose sum is σ = 163187136000. Its totient is φ = 38076988320.

The previous prime is 81533117513. The next prime is 81533117537. The reversal of 81533117528 is 82571133518.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3766688 + ... + 3788271.

It is an arithmetic number, because the mean of its divisors is an integer number (5099598000).

Almost surely, 2^81533117528 is an apocalyptic number.

It is an amenable number.

81533117528 is an abundant number, since it is smaller than the sum of its proper divisors (81654018472).

81533117528 is a wasteful number, since it uses less digits than its factorization.

81533117528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7555055 (or 7555051 counting only the distinct ones).

The product of its digits is 201600, while the sum is 44.

The spelling of 81533117528 in words is "eighty-one billion, five hundred thirty-three million, one hundred seventeen thousand, five hundred twenty-eight".