688305989 has 32 divisors (see below), whose sum is σ = 872448000. Its totient is φ = 540736560.

The previous prime is 688305971. The next prime is 688306001. The reversal of 688305989 is 989503886.

It is not a de Polignac number, because 688305989 - 2⁸ = 688305733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688305689) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 200324 + ... + 203730.

It is an arithmetic number, because the mean of its divisors is an integer number (27264000).

Almost surely, 2^688305989 is an apocalyptic number.

It is an amenable number.

688305989 is a deficient number, since it is larger than the sum of its proper divisors (184142011).

688305989 is a wasteful number, since it uses less digits than its factorization.

688305989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3478 (or 3464 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 56.

The square root of 688305989 is about 26235.5863094386. The cubic root of 688305989 is about 882.9318487657.

The spelling of 688305989 in words is "six hundred eighty-eight million, three hundred five thousand, nine hundred eighty-nine".