1971395716117 has 2 divisors, whose sum is σ = 1971395716118. Its totient is φ = 1971395716116.

The previous prime is 1971395716091. The next prime is 1971395716139. The reversal of 1971395716117 is 7116175931791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1824460727076 + 146934989041 = 1350726^2 + 383321^2 .

It is a cyclic number.

It is not a de Polignac number, because 1971395716117 - 2²³ = 1971387327509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1971395716517) 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, 985697858058 + 985697858059.

It is an arithmetic number, because the mean of its divisors is an integer number (985697858059).

Almost surely, 2^{1971395716117} is an apocalyptic number.

It is an amenable number.

1971395716117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1971395716117 is an equidigital number, since it uses as much as digits as its factorization.

1971395716117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2500470, while the sum is 58.

The spelling of 1971395716117 in words is "one trillion, nine hundred seventy-one billion, three hundred ninety-five million, seven hundred sixteen thousand, one hundred seventeen".