681872 has 20 divisors (see below), whose sum is σ = 1391280. Its totient is φ = 322848.

The previous prime is 681841. The next prime is 681883. The reversal of 681872 is 278186.

It is an unprimeable number.

681872 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, 818 + ... + 1425.

It is an arithmetic number, because the mean of its divisors is an integer number (69564).

2⁶⁸¹⁸⁷² is an apocalyptic number.

It is an amenable number.

681872 is an abundant number, since it is smaller than the sum of its proper divisors (709408).

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

681872 is a wasteful number, since it uses less digits than its factorization.

681872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2270 (or 2264 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 681872 is about 825.7554117292. The cubic root of 681872 is about 88.0172142632.

The spelling of 681872 in words is "six hundred eighty-one thousand, eight hundred seventy-two".