81992082517 has 4 divisors (see below), whose sum is σ = 82542365100. Its totient is φ = 81441799936.

The previous prime is 81992082463. The next prime is 81992082527. The reversal of 81992082517 is 71528029918.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 50379598116 + 31612484401 = 224454^2 + 177799^2 .

It is a cyclic number.

It is not a de Polignac number, because 81992082517 - 2¹⁵ = 81992049749 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 (81992082527) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 275141068 + ... + 275141365.

It is an arithmetic number, because the mean of its divisors is an integer number (20635591275).

Almost surely, 2^81992082517 is an apocalyptic number.

It is an amenable number.

81992082517 is a deficient number, since it is larger than the sum of its proper divisors (550282583).

81992082517 is a wasteful number, since it uses less digits than its factorization.

81992082517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550282582.

The product of its (nonzero) digits is 725760, while the sum is 52.

The spelling of 81992082517 in words is "eighty-one billion, nine hundred ninety-two million, eighty-two thousand, five hundred seventeen".