688889 has 2 divisors, whose sum is σ = 688890. Its totient is φ = 688888.

The previous prime is 688871. The next prime is 688907. The reversal of 688889 is 988886.

688889 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (688871) and next prime (688907).

It can be written as a sum of positive squares in only one way, i.e., 369664 + 319225 = 608^2 + 565^2 .

It is a cyclic number.

It is not a de Polignac number, because 688889 - 2¹² = 684793 is a prime.

688889 is a strobogrammatic number because it is the same when read upside-down.

It is a plaindrome in base 10.

It is not a weakly prime, because it can be changed into another prime (684889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344444 + 344445.

It is an arithmetic number, because the mean of its divisors is an integer number (344445).

2⁶⁸⁸⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

688889 is a deficient number, since it is larger than the sum of its proper divisors (1).

688889 is an equidigital number, since it uses as much as digits as its factorization.

688889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 47.

The square root of 688889 is about 829.9933734675. The cubic root of 688889 is about 88.3181066274.

The spelling of 688889 in words is "six hundred eighty-eight thousand, eight hundred eighty-nine".