685901 has 4 divisors (see below), whose sum is σ = 688704. Its totient is φ = 683100.

The previous prime is 685859. The next prime is 685907. The reversal of 685901 is 109586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685901 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a zygodrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 995 + ... + 1536.

It is an arithmetic number, because the mean of its divisors is an integer number (172176).

2⁶⁸⁵⁹⁰¹ is an apocalyptic number.

It is an amenable number.

685901 is a deficient number, since it is larger than the sum of its proper divisors (2803).

685901 is a wasteful number, since it uses less digits than its factorization.

685901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2802.

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

The square root of 685901 is about 828.1914029981. The cubic root of 685901 is about 88.1902306972.

The spelling of 685901 in words is "six hundred eighty-five thousand, nine hundred one".