81676109041 has 4 divisors (see below), whose sum is σ = 81680166052. Its totient is φ = 81672052032.

The previous prime is 81676109023. The next prime is 81676109069. The reversal of 81676109041 is 14090167618.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14090167618 = 2 ⋅7045083809.

It can be written as a sum of positive squares in 2 ways, for example, as 61254270016 + 20421839025 = 247496^2 + 142905^2 .

It is a cyclic number.

It is not a de Polignac number, because 81676109041 - 2²⁹ = 81139238129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81676109741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1998156 + ... + 2038621.

It is an arithmetic number, because the mean of its divisors is an integer number (20420041513).

Almost surely, 2^81676109041 is an apocalyptic number.

It is an amenable number.

81676109041 is a deficient number, since it is larger than the sum of its proper divisors (4057011).

81676109041 is a wasteful number, since it uses less digits than its factorization.

81676109041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4057010.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 81676109041 in words is "eighty-one billion, six hundred seventy-six million, one hundred nine thousand, forty-one".