681760 has 24 divisors (see below), whose sum is σ = 1611036. Its totient is φ = 272640.

The previous prime is 681731. The next prime is 681763. The reversal of 681760 is 67186.

It can be written as a sum of positive squares in 2 ways, for example, as 646416 + 35344 = 804^2 + 188^2 .

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (681763) 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, 1971 + ... + 2290.

2⁶⁸¹⁷⁶⁰ is an apocalyptic number.

It is an amenable number.

681760 is an abundant number, since it is smaller than the sum of its proper divisors (929276).

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

681760 is a wasteful number, since it uses less digits than its factorization.

681760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4276 (or 4268 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 681760 is about 825.6875922527. The cubic root of 681760 is about 88.0123949483.

It can be divided in two parts, 681 and 760, that added together give a palindrome (1441).

The spelling of 681760 in words is "six hundred eighty-one thousand, seven hundred sixty".