81116864693 has 8 divisors (see below), whose sum is σ = 82657231488. Its totient is φ = 79576863184.

The previous prime is 81116864683. The next prime is 81116864713. The reversal of 81116864693 is 39646861118.

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 81116864693 - 2²⁸ = 80848429237 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81116864603) 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 7 ways as a sum of consecutive naturals, for example, 379880 + ... + 553662.

It is an arithmetic number, because the mean of its divisors is an integer number (10332153936).

Almost surely, 2^81116864693 is an apocalyptic number.

It is an amenable number.

81116864693 is a deficient number, since it is larger than the sum of its proper divisors (1540366795).

81116864693 is a wasteful number, since it uses less digits than its factorization.

81116864693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182643.

The product of its digits is 1492992, while the sum is 53.

The spelling of 81116864693 in words is "eighty-one billion, one hundred sixteen million, eight hundred sixty-four thousand, six hundred ninety-three".