688746816 has 42 divisors (see below), whose sum is σ = 1974170042. Its totient is φ = 229582080.

The previous prime is 688746769. The next prime is 688746841. The reversal of 688746816 is 618647886.

It can be written as a sum of positive squares in only one way, i.e., 609892416 + 78854400 = 24696^2 + 8880^2 .

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 5 ways as a sum of consecutive naturals, for example, 597295 + ... + 598446.

Almost surely, 2^688746816 is an apocalyptic number.

It is an amenable number.

688746816 is an abundant number, since it is smaller than the sum of its proper divisors (1285423226).

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

688746816 is a wasteful number, since it uses less digits than its factorization.

688746816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1195759 (or 1195746 counting only the distinct ones).

The product of its digits is 3096576, while the sum is 54.

The square root of 688746816 is about 26243.9862825753. The cubic root of 688746816 is about 883.1203003853.

The spelling of 688746816 in words is "six hundred eighty-eight million, seven hundred forty-six thousand, eight hundred sixteen".