81197000812 has 6 divisors (see below), whose sum is σ = 142094751428. Its totient is φ = 40598500404.

The previous prime is 81197000761. The next prime is 81197000813. The reversal of 81197000812 is 21800079118.

It is not an unprimeable number, because it can be changed into a prime (81197000813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10149625098 + ... + 10149625105.

Almost surely, 2^81197000812 is an apocalyptic number.

It is an amenable number.

81197000812 is a deficient number, since it is larger than the sum of its proper divisors (60897750616).

81197000812 is a wasteful number, since it uses less digits than its factorization.

81197000812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20299250207 (or 20299250205 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 37.

The spelling of 81197000812 in words is "eighty-one billion, one hundred ninety-seven million, eight hundred twelve", and thus it is an aban number.