688899 has 8 divisors (see below), whose sum is σ = 922960. Its totient is φ = 457056.

The previous prime is 688889. The next prime is 688907. The reversal of 688899 is 998886.

It is a Cunningham number, because it is equal to 830²-1.

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

It is not a de Polignac number, because 688899 - 2⁵ = 688867 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417 + ... + 1245.

It is an arithmetic number, because the mean of its divisors is an integer number (115370).

2⁶⁸⁸⁸⁹⁹ is an apocalyptic number.

688899 is a deficient number, since it is larger than the sum of its proper divisors (234061).

688899 is a wasteful number, since it uses less digits than its factorization.

688899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1109.

The product of its digits is 248832, while the sum is 48.

The square root of 688899 is about 829.9993975901. Note that the first 3 decimals coincide. The cubic root of 688899 is about 88.3185339710.

The spelling of 688899 in words is "six hundred eighty-eight thousand, eight hundred ninety-nine".