81623161585 has 8 divisors (see below), whose sum is σ = 111940335936. Its totient is φ = 55970167920.

The previous prime is 81623161523. The next prime is 81623161597. The reversal of 81623161585 is 58516132618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81623161585 - 2⁹ = 81623161073 is a prime.

It is a Duffinian 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, 1166045131 + ... + 1166045200.

It is an arithmetic number, because the mean of its divisors is an integer number (13992541992).

Almost surely, 2^81623161585 is an apocalyptic number.

It is an amenable number.

81623161585 is a deficient number, since it is larger than the sum of its proper divisors (30317174351).

81623161585 is a wasteful number, since it uses less digits than its factorization.

81623161585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2332090343.

The product of its digits is 345600, while the sum is 46.

The spelling of 81623161585 in words is "eighty-one billion, six hundred twenty-three million, one hundred sixty-one thousand, five hundred eighty-five".