81169715071 has 4 divisors (see below), whose sum is σ = 83363491192. Its totient is φ = 78975938952.

The previous prime is 81169715009. The next prime is 81169715083. The reversal of 81169715071 is 17051796118.

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

It is a cyclic number.

It is not a de Polignac number, because 81169715071 - 2¹³ = 81169706879 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 (81169715971) 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, 1096888005 + ... + 1096888078.

It is an arithmetic number, because the mean of its divisors is an integer number (20840872798).

Almost surely, 2^81169715071 is an apocalyptic number.

81169715071 is a deficient number, since it is larger than the sum of its proper divisors (2193776121).

81169715071 is a wasteful number, since it uses less digits than its factorization.

81169715071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2193776120.

The product of its (nonzero) digits is 105840, while the sum is 46.

The spelling of 81169715071 in words is "eighty-one billion, one hundred sixty-nine million, seven hundred fifteen thousand, seventy-one".