681898 has 16 divisors (see below), whose sum is σ = 1192320. Its totient is φ = 286416.

The previous prime is 681883. The next prime is 681899. The reversal of 681898 is 898186.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 681898.

It is not an unprimeable number, because it can be changed into a prime (681899) 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 7 ways as a sum of consecutive naturals, for example, 283 + ... + 1201.

It is an arithmetic number, because the mean of its divisors is an integer number (74520).

2⁶⁸¹⁸⁹⁸ is an apocalyptic number.

681898 is a deficient number, since it is larger than the sum of its proper divisors (510422).

681898 is a wasteful number, since it uses less digits than its factorization.

681898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 981.

The product of its digits is 27648, while the sum is 40.

The square root of 681898 is about 825.7711547396. The cubic root of 681898 is about 88.0183329573.

The spelling of 681898 in words is "six hundred eighty-one thousand, eight hundred ninety-eight".