81729266097671 has 2 divisors, whose sum is σ = 81729266097672. Its totient is φ = 81729266097670.

The previous prime is 81729266097641. The next prime is 81729266097767. The reversal of 81729266097671 is 17679066292718.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81729266097671 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81729266097595 and 81729266097604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81729266097641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40864633048835 + 40864633048836.

It is an arithmetic number, because the mean of its divisors is an integer number (40864633048836).

Almost surely, 2^{81729266097671} is an apocalyptic number.

81729266097671 is a deficient number, since it is larger than the sum of its proper divisors (1).

81729266097671 is an equidigital number, since it uses as much as digits as its factorization.

81729266097671 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192036096, while the sum is 71.

The spelling of 81729266097671 in words is "eighty-one trillion, seven hundred twenty-nine billion, two hundred sixty-six million, ninety-seven thousand, six hundred seventy-one".