688361388 has 192 divisors, whose sum is σ = 1999613952. Its totient is φ = 181336320.

The previous prime is 688361381. The next prime is 688361407. The reversal of 688361388 is 883163886.

688361388 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Its product of digits (1327104) is a multiple of the sum of its prime factors (324).

It is a self number, because there is not a number n which added to its sum of digits gives 688361388.

It is not an unprimeable number, because it can be changed into a prime (688361381) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4222995 + ... + 4223157.

It is an arithmetic number, because the mean of its divisors is an integer number (10414656).

Almost surely, 2^688361388 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 688361388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (999806976).

688361388 is an abundant number, since it is smaller than the sum of its proper divisors (1311252564).

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

688361388 is a wasteful number, since it uses less digits than its factorization.

688361388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324 (or 322 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 51.

The square root of 688361388 is about 26236.6420869745. The cubic root of 688361388 is about 882.9555360162.

The spelling of 688361388 in words is "six hundred eighty-eight million, three hundred sixty-one thousand, three hundred eighty-eight".