685509317 has 4 divisors (see below), whose sum is σ = 688353996. Its totient is φ = 682664640.

The previous prime is 685509301. The next prime is 685509329. The reversal of 685509317 is 713905586.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 471150436 + 214358881 = 21706^2 + 14641^2 .

It is a cyclic number.

It is not a de Polignac number, because 685509317 - 2⁴ = 685509301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685509017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1421978 + ... + 1422459.

It is an arithmetic number, because the mean of its divisors is an integer number (172088499).

Almost surely, 2^685509317 is an apocalyptic number.

It is an amenable number.

685509317 is a deficient number, since it is larger than the sum of its proper divisors (2844679).

685509317 is a wasteful number, since it uses less digits than its factorization.

685509317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2844678.

The product of its (nonzero) digits is 226800, while the sum is 44.

The square root of 685509317 is about 26182.2328497781. The cubic root of 685509317 is about 881.7344052325.

The spelling of 685509317 in words is "six hundred eighty-five million, five hundred nine thousand, three hundred seventeen".