688647630 has 128 divisors (see below), whose sum is σ = 1879303680. Its totient is φ = 159971840.

The previous prime is 688647629. The next prime is 688647637. The reversal of 688647630 is 36746886.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 688647630.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688647637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2172232 + ... + 2172548.

It is an arithmetic number, because the mean of its divisors is an integer number (14682060).

Almost surely, 2^688647630 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688647630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (939651840).

688647630 is an abundant number, since it is smaller than the sum of its proper divisors (1190656050).

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

688647630 is a wasteful number, since it uses less digits than its factorization.

688647630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594.

The product of its (nonzero) digits is 1161216, while the sum is 48.

The square root of 688647630 is about 26242.0965244776. The cubic root of 688647630 is about 883.0779058154.

The spelling of 688647630 in words is "six hundred eighty-eight million, six hundred forty-seven thousand, six hundred thirty".