81641059013 has 2 divisors, whose sum is σ = 81641059014. Its totient is φ = 81641059012.

The previous prime is 81641059001. The next prime is 81641059067. The reversal of 81641059013 is 31095014618.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44523954049 + 37117104964 = 211007^2 + 192658^2 .

It is a cyclic number.

It is not a de Polignac number, because 81641059013 - 2⁶ = 81641058949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81641059613) 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, 40820529506 + 40820529507.

It is an arithmetic number, because the mean of its divisors is an integer number (40820529507).

Almost surely, 2^81641059013 is an apocalyptic number.

It is an amenable number.

81641059013 is a deficient number, since it is larger than the sum of its proper divisors (1).

81641059013 is an equidigital number, since it uses as much as digits as its factorization.

81641059013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 38.

The spelling of 81641059013 in words is "eighty-one billion, six hundred forty-one million, fifty-nine thousand, thirteen".