81079196881 has 2 divisors, whose sum is σ = 81079196882. Its totient is φ = 81079196880.

The previous prime is 81079196761. The next prime is 81079196893. The reversal of 81079196881 is 18869197018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80258890000 + 820306881 = 283300^2 + 28641^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81079196881 is a prime.

It is a super-2 number, since 2×81079196881² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81079199881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40539598440 + 40539598441.

It is an arithmetic number, because the mean of its divisors is an integer number (40539598441).

Almost surely, 2^81079196881 is an apocalyptic number.

It is an amenable number.

81079196881 is a deficient number, since it is larger than the sum of its proper divisors (1).

81079196881 is an equidigital number, since it uses as much as digits as its factorization.

81079196881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1741824, while the sum is 58.

The spelling of 81079196881 in words is "eighty-one billion, seventy-nine million, one hundred ninety-six thousand, eight hundred eighty-one".