81717023181493 has 16 divisors (see below), whose sum is σ = 93483431205120. Its totient is φ = 69973763328000.

The previous prime is 81717023181439. The next prime is 81717023181509. The reversal of 81717023181493 is 39418132071718.

It is a de Polignac number, because none of the positive numbers 2^k-81717023181493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81717023181413) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87654133 + ... + 88581493.

It is an arithmetic number, because the mean of its divisors is an integer number (5842714450320).

Almost surely, 2^{81717023181493} is an apocalyptic number.

It is an amenable number.

81717023181493 is a deficient number, since it is larger than the sum of its proper divisors (11766408023627).

81717023181493 is a wasteful number, since it uses less digits than its factorization.

81717023181493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 939828.

The product of its (nonzero) digits is 2032128, while the sum is 55.

The spelling of 81717023181493 in words is "eighty-one trillion, seven hundred seventeen billion, twenty-three million, one hundred eighty-one thousand, four hundred ninety-three".