668189632 has 56 divisors (see below), whose sum is σ = 1471086720. Its totient is φ = 298556160.

The previous prime is 668189617. The next prime is 668189633. The reversal of 668189632 is 236981866.

It is a happy number.

668189632 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668189633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33493 + ... + 49579.

Almost surely, 2^668189632 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668189632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (735543360).

668189632 is an abundant number, since it is smaller than the sum of its proper divisors (802897088).

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

668189632 is a wasteful number, since it uses less digits than its factorization.

668189632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16169 (or 16159 counting only the distinct ones).

The product of its digits is 746496, while the sum is 49.

The square root of 668189632 is about 25849.3642475013. The cubic root of 668189632 is about 874.2451752093.

The spelling of 668189632 in words is "six hundred sixty-eight million, one hundred eighty-nine thousand, six hundred thirty-two".