688803840 has 312 divisors, whose sum is σ = 2476368648. Its totient is φ = 176947200.

The previous prime is 688803823. The next prime is 688803851. The reversal of 688803840 is 48308886.

It can be written as a sum of positive squares in 4 ways, for example, as 383533056 + 305270784 = 19584^2 + 17472^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6819790 + ... + 6819890.

It is an arithmetic number, because the mean of its divisors is an integer number (7937079).

Almost surely, 2^688803840 is an apocalyptic number.

688803840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688803840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1238184324).

688803840 is an abundant number, since it is smaller than the sum of its proper divisors (1787564808).

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

688803840 is a wasteful number, since it uses less digits than its factorization.

688803840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 45.

The square root of 688803840 is about 26245.0726804099. The cubic root of 688803840 is about 883.1446720224.

The spelling of 688803840 in words is "six hundred eighty-eight million, eight hundred three thousand, eight hundred forty".