81197000811 has 6 divisors (see below), whose sum is σ = 117284556740. Its totient is φ = 54131333868.

The previous prime is 81197000761. The next prime is 81197000813. The reversal of 81197000811 is 11800079118.

It is a happy number.

It is not a de Polignac number, because 81197000811 - 2¹⁰ = 81196999787 is a prime.

It is a Duffinian number.

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

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4510944481 + ... + 4510944498.

Almost surely, 2^81197000811 is an apocalyptic number.

81197000811 is a deficient number, since it is larger than the sum of its proper divisors (36087555929).

81197000811 is a wasteful number, since it uses less digits than its factorization.

81197000811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9021888985 (or 9021888982 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 36.

Adding to 81197000811 its reverse (11800079118), we get a palindrome (92997079929).

The spelling of 81197000811 in words is "eighty-one billion, one hundred ninety-seven million, eight hundred eleven", and thus it is an aban number.