681678 has 12 divisors (see below), whose sum is σ = 1477008. Its totient is φ = 227220.

The previous prime is 681677. The next prime is 681689. The reversal of 681678 is 876186.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18918 + ... + 18953.

It is an arithmetic number, because the mean of its divisors is an integer number (123084).

2⁶⁸¹⁶⁷⁸ is an apocalyptic number.

681678 is an abundant number, since it is smaller than the sum of its proper divisors (795330).

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

681678 is a wasteful number, since it uses less digits than its factorization.

681678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37879 (or 37876 counting only the distinct ones).

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

The square root of 681678 is about 825.6379351750. The cubic root of 681678 is about 88.0088661866.

The spelling of 681678 in words is "six hundred eighty-one thousand, six hundred seventy-eight".