687889 has 4 divisors (see below), whose sum is σ = 698224. Its totient is φ = 677556.

The previous prime is 687847. The next prime is 687893. The reversal of 687889 is 988786.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 687889 - 2¹⁵ = 655121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687809) 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 3 ways as a sum of consecutive naturals, for example, 5067 + ... + 5200.

It is an arithmetic number, because the mean of its divisors is an integer number (174556).

2⁶⁸⁷⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

687889 is a deficient number, since it is larger than the sum of its proper divisors (10335).

687889 is a wasteful number, since it uses less digits than its factorization.

687889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10334.

The product of its digits is 193536, while the sum is 46.

The square root of 687889 is about 829.3907402425. The cubic root of 687889 is about 88.2753513719.

The spelling of 687889 in words is "six hundred eighty-seven thousand, eight hundred eighty-nine".