688545444 has 12 divisors (see below), whose sum is σ = 1606606064. Its totient is φ = 229515144.

The previous prime is 688545443. The next prime is 688545467. The reversal of 688545444 is 444545886.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 688545393 and 688545402.

It is not an unprimeable number, because it can be changed into a prime (688545443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28689382 + ... + 28689405.

Almost surely, 2^688545444 is an apocalyptic number.

It is an amenable number.

688545444 is an abundant number, since it is smaller than the sum of its proper divisors (918060620).

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

688545444 is a wasteful number, since it uses less digits than its factorization.

688545444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57378794 (or 57378792 counting only the distinct ones).

The product of its digits is 2457600, while the sum is 48.

The square root of 688545444 is about 26240.1494660377. The cubic root of 688545444 is about 883.0342247131.

The spelling of 688545444 in words is "six hundred eighty-eight million, five hundred forty-five thousand, four hundred forty-four".