687698 has 8 divisors (see below), whose sum is σ = 1125360. Its totient is φ = 312580.

The previous prime is 687691. The next prime is 687707. The reversal of 687698 is 896786.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (687691) by changing a digit.

687698 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 15608 + ... + 15651.

It is an arithmetic number, because the mean of its divisors is an integer number (140670).

2⁶⁸⁷⁶⁹⁸ is an apocalyptic number.

687698 is a deficient number, since it is larger than the sum of its proper divisors (437662).

687698 is a wasteful number, since it uses less digits than its factorization.

687698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31272.

The product of its digits is 145152, while the sum is 44.

The square root of 687698 is about 829.2755874858. The cubic root of 687698 is about 88.2671804059.

The spelling of 687698 in words is "six hundred eighty-seven thousand, six hundred ninety-eight".