668608992 has 240 divisors, whose sum is σ = 2081261952. Its totient is φ = 210263040.

The previous prime is 668608987. The next prime is 668608999. The reversal of 668608992 is 299806866.

668608992 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668608999) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4258578 + ... + 4258734.

Almost surely, 2^668608992 is an apocalyptic number.

668608992 is a gapful number since it is divisible by the number (62) 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 668608992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1040630976).

668608992 is an abundant number, since it is smaller than the sum of its proper divisors (1412652960).

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

668608992 is a wasteful number, since it uses less digits than its factorization.

668608992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The square root of 668608992 is about 25857.4745866645. The cubic root of 668608992 is about 874.4280308775.

The spelling of 668608992 in words is "six hundred sixty-eight million, six hundred eight thousand, nine hundred ninety-two".