81641063113 has 2 divisors, whose sum is σ = 81641063114. Its totient is φ = 81641063112.

The previous prime is 81641063099. The next prime is 81641063129. The reversal of 81641063113 is 31136014618.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65233246464 + 16407816649 = 255408^2 + 128093^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81641063113 is a prime.

It is not a weakly prime, because it can be changed into another prime (81641063183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40820531556 + 40820531557.

It is an arithmetic number, because the mean of its divisors is an integer number (40820531557).

Almost surely, 2^81641063113 is an apocalyptic number.

It is an amenable number.

81641063113 is a deficient number, since it is larger than the sum of its proper divisors (1).

81641063113 is an equidigital number, since it uses as much as digits as its factorization.

81641063113 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 34.

The spelling of 81641063113 in words is "eighty-one billion, six hundred forty-one million, sixty-three thousand, one hundred thirteen".