668055406320 has 240 divisors, whose sum is σ = 2297813561472. Its totient is φ = 173847098880.

The previous prime is 668055406243. The next prime is 668055406429. The reversal of 668055406320 is 23604550866.

668055406320 is a `hidden beast` number, since 6 + 6 + 8 + 0 + 5 + 5 + 4 + 0 + 632 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36244947 + ... + 36263373.

Almost surely, 2^668055406320 is an apocalyptic number.

668055406320 is a gapful number since it is divisible by the number (60) 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 668055406320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1148906780736).

668055406320 is an abundant number, since it is smaller than the sum of its proper divisors (1629758155152).

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

668055406320 is a wasteful number, since it uses less digits than its factorization.

668055406320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19660 (or 19651 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

The spelling of 668055406320 in words is "six hundred sixty-eight billion, fifty-five million, four hundred six thousand, three hundred twenty".