81973694829 has 16 divisors (see below), whose sum is σ = 123900862400. Its totient is φ = 47790331776.

The previous prime is 81973694827. The next prime is 81973694837. The reversal of 81973694829 is 92849637918.

It is not a de Polignac number, because 81973694829 - 2¹ = 81973694827 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 81973694829.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81973694827) 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, 55312144 + ... + 55313625.

It is an arithmetic number, because the mean of its divisors is an integer number (7743803900).

Almost surely, 2^81973694829 is an apocalyptic number.

It is an amenable number.

81973694829 is a deficient number, since it is larger than the sum of its proper divisors (41927167571).

81973694829 is a wasteful number, since it uses less digits than its factorization.

81973694829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110625804.

The product of its digits is 47029248, while the sum is 66.

The spelling of 81973694829 in words is "eighty-one billion, nine hundred seventy-three million, six hundred ninety-four thousand, eight hundred twenty-nine".