688813820 has 24 divisors (see below), whose sum is σ = 1531598544. Its totient is φ = 259318016.

The previous prime is 688813789. The next prime is 688813841. The reversal of 688813820 is 28318886.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1012622 + ... + 1013301.

It is an arithmetic number, because the mean of its divisors is an integer number (63816606).

Almost surely, 2^688813820 is an apocalyptic number.

It is an amenable number.

688813820 is an abundant number, since it is smaller than the sum of its proper divisors (842784724).

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

688813820 is a wasteful number, since it uses less digits than its factorization.

688813820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2025949 (or 2025947 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 44.

The square root of 688813820 is about 26245.2628106483. The cubic root of 688813820 is about 883.1489372625.

The spelling of 688813820 in words is "six hundred eighty-eight million, eight hundred thirteen thousand, eight hundred twenty".