685358857 has 6 divisors (see below), whose sum is σ = 690647834. Its totient is φ = 680110080.

The previous prime is 685358833. The next prime is 685358887. The reversal of 685358857 is 758853586.

It can be written as a sum of positive squares in only one way, i.e., 659256976 + 26101881 = 25676^2 + 5109^2 .

It is not a de Polignac number, because 685358857 - 2¹⁹ = 684834569 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 685358798 and 685358807.

It is not an unprimeable number, because it can be changed into a prime (685358887) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2808 + ... + 37129.

Almost surely, 2^685358857 is an apocalyptic number.

It is an amenable number.

685358857 is a deficient number, since it is larger than the sum of its proper divisors (5288977).

685358857 is an equidigital number, since it uses as much as digits as its factorization.

685358857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40199 (or 40068 counting only the distinct ones).

The product of its digits is 8064000, while the sum is 55.

The square root of 685358857 is about 26179.3593695491. The cubic root of 685358857 is about 881.6698909302.

The spelling of 685358857 in words is "six hundred eighty-five million, three hundred fifty-eight thousand, eight hundred fifty-seven".