81611863432 has 16 divisors (see below), whose sum is σ = 166933357200. Its totient is φ = 37096301520.

The previous prime is 81611863409. The next prime is 81611863441. The reversal of 81611863432 is 23436811618.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 463703682 + ... + 463703857.

It is an arithmetic number, because the mean of its divisors is an integer number (10433334825).

Almost surely, 2^81611863432 is an apocalyptic number.

It is an amenable number.

81611863432 is an abundant number, since it is smaller than the sum of its proper divisors (85321493768).

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

81611863432 is a wasteful number, since it uses less digits than its factorization.

81611863432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 927407556 (or 927407552 counting only the distinct ones).

The product of its digits is 165888, while the sum is 43.

It can be divided in two parts, 8161186 and 3432, that added together give a palindrome (8164618).

The spelling of 81611863432 in words is "eighty-one billion, six hundred eleven million, eight hundred sixty-three thousand, four hundred thirty-two".