81729266099671 has 2 divisors, whose sum is σ = 81729266099672. Its totient is φ = 81729266099670.

The previous prime is 81729266099653. The next prime is 81729266099743. The reversal of 81729266099671 is 17699066292718.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81729266099671 - 2²³ = 81729257711063 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81729266099594 and 81729266099603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81729266097671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40864633049835 + 40864633049836.

It is an arithmetic number, because the mean of its divisors is an integer number (40864633049836).

Almost surely, 2^{81729266099671} is an apocalyptic number.

81729266099671 is a deficient number, since it is larger than the sum of its proper divisors (1).

81729266099671 is an equidigital number, since it uses as much as digits as its factorization.

81729266099671 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 246903552, while the sum is 73.

The spelling of 81729266099671 in words is "eighty-one trillion, seven hundred twenty-nine billion, two hundred sixty-six million, ninety-nine thousand, six hundred seventy-one".