81886657799 has 2 divisors, whose sum is σ = 81886657800. Its totient is φ = 81886657798.

The previous prime is 81886657777. The next prime is 81886657813. The reversal of 81886657799 is 99775668818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81886657799 - 2⁸ = 81886657543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81886657199) 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, 40943328899 + 40943328900.

It is an arithmetic number, because the mean of its divisors is an integer number (40943328900).

Almost surely, 2^81886657799 is an apocalyptic number.

81886657799 is a deficient number, since it is larger than the sum of its proper divisors (1).

81886657799 is an equidigital number, since it uses as much as digits as its factorization.

81886657799 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 365783040, while the sum is 74.

The spelling of 81886657799 in words is "eighty-one billion, eight hundred eighty-six million, six hundred fifty-seven thousand, seven hundred ninety-nine".