397688692643609 has 2 divisors, whose sum is σ = 397688692643610. Its totient is φ = 397688692643608.

The previous prime is 397688692643563. The next prime is 397688692643687. The reversal of 397688692643609 is 906346296886793.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 235797983161225 + 161890709482384 = 15355715^2 + 12723628^2 .

It is a cyclic number.

It is not a de Polignac number, because 397688692643609 - 2²⁰ = 397688691595033 is a prime.

It is not a weakly prime, because it can be changed into another prime (397688692643909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198844346321804 + 198844346321805.

It is an arithmetic number, because the mean of its divisors is an integer number (198844346321805).

Almost surely, 2^{397688692643609} is an apocalyptic number.

It is an amenable number.

397688692643609 is a deficient number, since it is larger than the sum of its proper divisors (1).

397688692643609 is an equidigital number, since it uses as much as digits as its factorization.

397688692643609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30474952704, while the sum is 86.

The spelling of 397688692643609 in words is "three hundred ninety-seven trillion, six hundred eighty-eight billion, six hundred ninety-two million, six hundred forty-three thousand, six hundred nine".