81917116165 has 8 divisors (see below), whose sum is σ = 98327813760. Its totient is φ = 65515510032.

The previous prime is 81917116153. The next prime is 81917116187. The reversal of 81917116165 is 56161171918.

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

It is a cyclic number.

It is not a de Polignac number, because 81917116165 - 2⁹ = 81917115653 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2253025 + ... + 2289094.

It is an arithmetic number, because the mean of its divisors is an integer number (12290976720).

Almost surely, 2^81917116165 is an apocalyptic number.

It is an amenable number.

81917116165 is a deficient number, since it is larger than the sum of its proper divisors (16410697595).

81917116165 is a wasteful number, since it uses less digits than its factorization.

81917116165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4545731.

The product of its digits is 90720, while the sum is 46.

The spelling of 81917116165 in words is "eighty-one billion, nine hundred seventeen million, one hundred sixteen thousand, one hundred sixty-five".