81228938811071 has 2 divisors, whose sum is σ = 81228938811072. Its totient is φ = 81228938811070.

The previous prime is 81228938811067. The next prime is 81228938811151. The reversal of 81228938811071 is 17011883982218.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81228938811071 - 2² = 81228938811067 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81228938811071.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81228938811001) 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 as a sum of consecutive naturals, namely, 40614469405535 + 40614469405536.

It is an arithmetic number, because the mean of its divisors is an integer number (40614469405536).

Almost surely, 2^{81228938811071} is an apocalyptic number.

81228938811071 is a deficient number, since it is larger than the sum of its proper divisors (1).

81228938811071 is an equidigital number, since it uses as much as digits as its factorization.

81228938811071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3096576, while the sum is 59.

The spelling of 81228938811071 in words is "eighty-one trillion, two hundred twenty-eight billion, nine hundred thirty-eight million, eight hundred eleven thousand, seventy-one".