71161809892081 has 2 divisors, whose sum is σ = 71161809892082. Its totient is φ = 71161809892080.

The previous prime is 71161809892027. The next prime is 71161809892223. The reversal of 71161809892081 is 18029890816117.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66367352251456 + 4794457640625 = 8146616^2 + 2189625^2 .

It is a cyclic number.

It is not a de Polignac number, because 71161809892081 - 2³⁹ = 70612054078193 is a prime.

It is a super-2 number, since 2×71161809892081² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71161809812081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35580904946040 + 35580904946041.

It is an arithmetic number, because the mean of its divisors is an integer number (35580904946041).

Almost surely, 2^{71161809892081} is an apocalyptic number.

It is an amenable number.

71161809892081 is a deficient number, since it is larger than the sum of its proper divisors (1).

71161809892081 is an equidigital number, since it uses as much as digits as its factorization.

71161809892081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3483648, while the sum is 61.

The spelling of 71161809892081 in words is "seventy-one trillion, one hundred sixty-one billion, eight hundred nine million, eight hundred ninety-two thousand, eighty-one".