81404964101 has 2 divisors, whose sum is σ = 81404964102. Its totient is φ = 81404964100.

The previous prime is 81404964079. The next prime is 81404964127. The reversal of 81404964101 is 10146940418.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74411656225 + 6993307876 = 272785^2 + 83626^2 .

It is a cyclic number.

It is not a de Polignac number, because 81404964101 - 2¹⁸ = 81404701957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81404964701) 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, 40702482050 + 40702482051.

It is an arithmetic number, because the mean of its divisors is an integer number (40702482051).

Almost surely, 2^81404964101 is an apocalyptic number.

It is an amenable number.

81404964101 is a deficient number, since it is larger than the sum of its proper divisors (1).

81404964101 is an equidigital number, since it uses as much as digits as its factorization.

81404964101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 38.

The spelling of 81404964101 in words is "eighty-one billion, four hundred four million, nine hundred sixty-four thousand, one hundred one".