685220692397 has 2 divisors, whose sum is σ = 685220692398. Its totient is φ = 685220692396.

The previous prime is 685220692369. The next prime is 685220692417. The reversal of 685220692397 is 793296022586.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 611678845801 + 73541846596 = 782099^2 + 271186^2 .

It is a cyclic number.

It is not a de Polignac number, because 685220692397 - 2²⁴ = 685203915181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685220292397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342610346198 + 342610346199.

It is an arithmetic number, because the mean of its divisors is an integer number (342610346199).

Almost surely, 2^685220692397 is an apocalyptic number.

It is an amenable number.

685220692397 is a deficient number, since it is larger than the sum of its proper divisors (1).

685220692397 is an equidigital number, since it uses as much as digits as its factorization.

685220692397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19595520, while the sum is 59.

The spelling of 685220692397 in words is "six hundred eighty-five billion, two hundred twenty million, six hundred ninety-two thousand, three hundred ninety-seven".