678681 has 12 divisors (see below), whose sum is σ = 994708. Its totient is φ = 445824.

The previous prime is 678659. The next prime is 678719. The reversal of 678681 is 186876.

678681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 549081 + 129600 = 741^2 + 360^2 .

It is not a de Polignac number, because 678681 - 2⁵ = 678649 is a prime.

It is a super-2 number, since 2×678681² = 921215799522, which contains 22 as substring.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 678681.

It is not an unprimeable number, because it can be changed into a prime (678611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 141 + ... + 1173.

2⁶⁷⁸⁶⁸¹ is an apocalyptic number.

It is an amenable number.

678681 is a deficient number, since it is larger than the sum of its proper divisors (316027).

678681 is a wasteful number, since it uses less digits than its factorization.

678681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112 (or 1109 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 678681 is about 823.8209756980. The cubic root of 678681 is about 87.8796995990.

It can be divided in two parts, 6 and 78681, that added together give a palindrome (78687).

The spelling of 678681 in words is "six hundred seventy-eight thousand, six hundred eighty-one".