685397117 has 2 divisors, whose sum is σ = 685397118. Its totient is φ = 685397116.

The previous prime is 685397059. The next prime is 685397137. The reversal of 685397117 is 711793586.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 646634041 + 38763076 = 25429^2 + 6226^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685397117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685397137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342698558 + 342698559.

It is an arithmetic number, because the mean of its divisors is an integer number (342698559).

Almost surely, 2^685397117 is an apocalyptic number.

It is an amenable number.

685397117 is a deficient number, since it is larger than the sum of its proper divisors (1).

685397117 is an equidigital number, since it uses as much as digits as its factorization.

685397117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 317520, while the sum is 47.

The square root of 685397117 is about 26180.0900876983. The cubic root of 685397117 is about 881.6862969643.

The spelling of 685397117 in words is "six hundred eighty-five million, three hundred ninety-seven thousand, one hundred seventeen".