81929711193 has 32 divisors (see below), whose sum is σ = 120096749952. Its totient is φ = 49268774400.

The previous prime is 81929711183. The next prime is 81929711249. The reversal of 81929711193 is 39111792918.

It is not a de Polignac number, because 81929711193 - 2¹⁰ = 81929710169 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81929711113) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 19225683 + ... + 19229943.

It is an arithmetic number, because the mean of its divisors is an integer number (3753023436).

Almost surely, 2^81929711193 is an apocalyptic number.

It is an amenable number.

81929711193 is a deficient number, since it is larger than the sum of its proper divisors (38167038759).

81929711193 is a wasteful number, since it uses less digits than its factorization.

81929711193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8665.

The product of its digits is 244944, while the sum is 51.

The spelling of 81929711193 in words is "eighty-one billion, nine hundred twenty-nine million, seven hundred eleven thousand, one hundred ninety-three".