81071011361 has 2 divisors, whose sum is σ = 81071011362. Its totient is φ = 81071011360.

The previous prime is 81071011349. The next prime is 81071011421. The reversal of 81071011361 is 16311017018.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80392096225 + 678915136 = 283535^2 + 26056^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81071011361 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (81071011261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40535505680 + 40535505681.

It is an arithmetic number, because the mean of its divisors is an integer number (40535505681).

Almost surely, 2^81071011361 is an apocalyptic number.

It is an amenable number.

81071011361 is a deficient number, since it is larger than the sum of its proper divisors (1).

81071011361 is an equidigital number, since it uses as much as digits as its factorization.

81071011361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 29.

Adding to 81071011361 its reverse (16311017018), we get a palindrome (97382028379).

The spelling of 81071011361 in words is "eighty-one billion, seventy-one million, eleven thousand, three hundred sixty-one".