668619828 has 36 divisors (see below), whose sum is σ = 1694012320. Its totient is φ = 222360336.

The previous prime is 668619827. The next prime is 668619929. The reversal of 668619828 is 828916866.

It is a happy number.

668619828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668619827) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5350 + ... + 36957.

Almost surely, 2^668619828 is an apocalyptic number.

It is an amenable number.

668619828 is an abundant number, since it is smaller than the sum of its proper divisors (1025392492).

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

668619828 is a wasteful number, since it uses less digits than its factorization.

668619828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42756 (or 42751 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 54.

The square root of 668619828 is about 25857.6841190390. The cubic root of 668619828 is about 874.4327547401.

The spelling of 668619828 in words is "six hundred sixty-eight million, six hundred nineteen thousand, eight hundred twenty-eight".