81973292712 has 16 divisors (see below), whose sum is σ = 204933231840. Its totient is φ = 27324430896.

The previous prime is 81973292699. The next prime is 81973292719. The reversal of 81973292712 is 21729237918.

It is not an unprimeable number, because it can be changed into a prime (81973292719) 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, 1707776908 + ... + 1707776955.

It is an arithmetic number, because the mean of its divisors is an integer number (12808326990).

Almost surely, 2^81973292712 is an apocalyptic number.

It is an amenable number.

81973292712 is an abundant number, since it is smaller than the sum of its proper divisors (122959939128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81973292712 is a wasteful number, since it uses less digits than its factorization.

81973292712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3415553872 (or 3415553868 counting only the distinct ones).

The product of its digits is 762048, while the sum is 51.

The spelling of 81973292712 in words is "eighty-one billion, nine hundred seventy-three million, two hundred ninety-two thousand, seven hundred twelve".