688911 has 4 divisors (see below), whose sum is σ = 918552. Its totient is φ = 459272.

The previous prime is 688907. The next prime is 688939. The reversal of 688911 is 119886.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 688911 - 2² = 688907 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114816 + ... + 114821.

It is an arithmetic number, because the mean of its divisors is an integer number (229638).

2⁶⁸⁸⁹¹¹ is an apocalyptic number.

688911 is a deficient number, since it is larger than the sum of its proper divisors (229641).

688911 is a wasteful number, since it uses less digits than its factorization.

688911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229640.

The product of its digits is 3456, while the sum is 33.

The square root of 688911 is about 830.0066264796. The cubic root of 688911 is about 88.3190467777.

The spelling of 688911 in words is "six hundred eighty-eight thousand, nine hundred eleven".