688899328 has 72 divisors (see below), whose sum is σ = 1487831688. Its totient is φ = 316465152.

The previous prime is 688899317. The next prime is 688899331. The reversal of 688899328 is 823998886.

It can be written as a sum of positive squares in 4 ways, for example, as 31899904 + 656999424 = 5648^2 + 25632^2 .

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1054650 + ... + 1055302.

It is an arithmetic number, because the mean of its divisors is an integer number (20664329).

Almost surely, 2^688899328 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688899328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (743915844).

688899328 is an abundant number, since it is smaller than the sum of its proper divisors (798932360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688899328 is a wasteful number, since it uses less digits than its factorization.

688899328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 999 (or 985 counting only the distinct ones).

The product of its digits is 11943936, while the sum is 61.

The square root of 688899328 is about 26246.8917778849. The cubic root of 688899328 is about 883.1854798775.

The spelling of 688899328 in words is "six hundred eighty-eight million, eight hundred ninety-nine thousand, three hundred twenty-eight".