81466522271 has 4 divisors (see below), whose sum is σ = 81468783000. Its totient is φ = 81464261544.

The previous prime is 81466522253. The next prime is 81466522303. The reversal of 81466522271 is 17222566418.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81466522271 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 (81466522201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1075421 + ... + 1148678.

It is an arithmetic number, because the mean of its divisors is an integer number (20367195750).

Almost surely, 2^81466522271 is an apocalyptic number.

81466522271 is a deficient number, since it is larger than the sum of its proper divisors (2260729).

81466522271 is a wasteful number, since it uses less digits than its factorization.

81466522271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2260728.

The product of its digits is 322560, while the sum is 44.

The spelling of 81466522271 in words is "eighty-one billion, four hundred sixty-six million, five hundred twenty-two thousand, two hundred seventy-one".