197917255717 has 2 divisors, whose sum is σ = 197917255718. Its totient is φ = 197917255716.

The previous prime is 197917255709. The next prime is 197917255729. The reversal of 197917255717 is 717552719791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 178308574756 + 19608680961 = 422266^2 + 140031^2 .

It is a cyclic number.

It is not a de Polignac number, because 197917255717 - 2³ = 197917255709 is a prime.

It is a super-2 number, since 2×197917255717² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197917250717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98958627858 + 98958627859.

It is an arithmetic number, because the mean of its divisors is an integer number (98958627859).

Almost surely, 2^197917255717 is an apocalyptic number.

It is an amenable number.

197917255717 is a deficient number, since it is larger than the sum of its proper divisors (1).

197917255717 is an equidigital number, since it uses as much as digits as its factorization.

197917255717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9724050, while the sum is 61.

The spelling of 197917255717 in words is "one hundred ninety-seven billion, nine hundred seventeen million, two hundred fifty-five thousand, seven hundred seventeen".