668761184520 has 1792 divisors, whose sum is σ = 2919180902400. Its totient is φ = 135242680320.

The previous prime is 668761184489. The next prime is 668761184561. The reversal of 668761184520 is 25481167866.

668761184520 is a `hidden beast` number, since 6 + 6 + 8 + 76 + 118 + 452 + 0 = 666.

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

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 447 ways as a sum of consecutive naturals, for example, 1822237377 + ... + 1822237743.

It is an arithmetic number, because the mean of its divisors is an integer number (1629007200).

Almost surely, 2^668761184520 is an apocalyptic number.

668761184520 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 668761184520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1459590451200).

668761184520 is an abundant number, since it is smaller than the sum of its proper divisors (2250419717880).

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

668761184520 is a wasteful number, since it uses less digits than its factorization.

668761184520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462 (or 443 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 54.

The spelling of 668761184520 in words is "six hundred sixty-eight billion, seven hundred sixty-one million, one hundred eighty-four thousand, five hundred twenty".