680840 has 16 divisors (see below), whose sum is σ = 1531980. Its totient is φ = 272320.

The previous prime is 680831. The next prime is 680857. The reversal of 680840 is 48086.

It can be written as a sum of positive squares in 2 ways, for example, as 643204 + 37636 = 802^2 + 194^2 .

It is an unprimeable number.

680840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8471 + ... + 8550.

2⁶⁸⁰⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

680840 is an abundant number, since it is smaller than the sum of its proper divisors (851140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

680840 is a wasteful number, since it uses less digits than its factorization.

680840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17032 (or 17028 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 680840 is about 825.1302927417. The cubic root of 680840 is about 87.9727877293.

The spelling of 680840 in words is "six hundred eighty thousand, eight hundred forty".