81486166273 has 4 divisors (see below), whose sum is σ = 81491777028. Its totient is φ = 81480555520.

The previous prime is 81486166271. The next prime is 81486166277. The reversal of 81486166273 is 37266168418.

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 39867310224 + 41618856049 = 199668^2 + 204007^2 .

It is a cyclic number.

It is not a de Polignac number, because 81486166273 - 2¹ = 81486166271 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81486166273.

It is not an unprimeable number, because it can be changed into a prime (81486166271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2783536 + ... + 2812657.

It is an arithmetic number, because the mean of its divisors is an integer number (20372944257).

Almost surely, 2^81486166273 is an apocalyptic number.

It is an amenable number.

81486166273 is a deficient number, since it is larger than the sum of its proper divisors (5610755).

81486166273 is a wasteful number, since it uses less digits than its factorization.

81486166273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5610754.

The product of its digits is 2322432, while the sum is 52.

The spelling of 81486166273 in words is "eighty-one billion, four hundred eighty-six million, one hundred sixty-six thousand, two hundred seventy-three".