668080747376640 has 2080 divisors, whose sum is σ = 2655292172081472. Its totient is φ = 159634685952000.

The previous prime is 668080747376587. The next prime is 668080747376701. The reversal of 668080747376640 is 46673747080866.

668080747376640 is a `hidden beast` number, since 6 + 6 + 8 + 0 + 80 + 7 + 473 + 76 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2080).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 186562619650 + ... + 186562623230.

Almost surely, 2^{668080747376640} is an apocalyptic number.

668080747376640 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 668080747376640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1327646086040736).

668080747376640 is an abundant number, since it is smaller than the sum of its proper divisors (1987211424704832).

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

668080747376640 is a wasteful number, since it uses less digits than its factorization.

668080747376640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3887 (or 3856 counting only the distinct ones).

The product of its (nonzero) digits is 1365590016, while the sum is 72.

The spelling of 668080747376640 in words is "six hundred sixty-eight trillion, eighty billion, seven hundred forty-seven million, three hundred seventy-six thousand, six hundred forty".