81608562671 has 16 divisors (see below), whose sum is σ = 90526256640. Its totient is φ = 73219687200.

The previous prime is 81608562667. The next prime is 81608562677. The reversal of 81608562671 is 17626580618.

It is a cyclic number.

It is not a de Polignac number, because 81608562671 - 2² = 81608562667 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 (81608562677) 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, 880355 + ... + 968628.

It is an arithmetic number, because the mean of its divisors is an integer number (5657891040).

Almost surely, 2^81608562671 is an apocalyptic number.

81608562671 is a deficient number, since it is larger than the sum of its proper divisors (8917693969).

81608562671 is a wasteful number, since it uses less digits than its factorization.

81608562671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1849126.

The product of its (nonzero) digits is 967680, while the sum is 50.

The spelling of 81608562671 in words is "eighty-one billion, six hundred eight million, five hundred sixty-two thousand, six hundred seventy-one".