685091 has 8 divisors (see below), whose sum is σ = 760368. Its totient is φ = 612000.

The previous prime is 685081. The next prime is 685093. The reversal of 685091 is 190586.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685091 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685093) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161 + ... + 1181.

It is an arithmetic number, because the mean of its divisors is an integer number (95046).

2⁶⁸⁵⁰⁹¹ is an apocalyptic number.

685091 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

685091 is a deficient number, since it is larger than the sum of its proper divisors (75277).

685091 is a wasteful number, since it uses less digits than its factorization.

685091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 685091 is about 827.7022411471. The cubic root of 685091 is about 88.1555015722.

The spelling of 685091 in words is "six hundred eighty-five thousand, ninety-one".