668257778430 has 384 divisors, whose sum is σ = 2099072102400. Its totient is φ = 151364505600.

The previous prime is 668257778423. The next prime is 668257778449. The reversal of 668257778430 is 34877752866.

668257778430 is a `hidden beast` number, since 6 + 6 + 82 + 57 + 7 + 78 + 430 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 24016366 + ... + 24044174.

It is an arithmetic number, because the mean of its divisors is an integer number (5466333600).

Almost surely, 2^668257778430 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668257778430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1049536051200).

668257778430 is an abundant number, since it is smaller than the sum of its proper divisors (1430814323970).

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

668257778430 is a wasteful number, since it uses less digits than its factorization.

668257778430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27902 (or 27890 counting only the distinct ones).

The product of its (nonzero) digits is 94832640, while the sum is 63.

The spelling of 668257778430 in words is "six hundred sixty-eight billion, two hundred fifty-seven million, seven hundred seventy-eight thousand, four hundred thirty".