668493018720 has 144 divisors (see below), whose sum is σ = 2281652558640. Its totient is φ = 178231974912.

The previous prime is 668493018719. The next prime is 668493018763. The reversal of 668493018720 is 27810394866.

668493018720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8351046 + ... + 8430714.

It is an arithmetic number, because the mean of its divisors is an integer number (15844809435).

Almost surely, 2^668493018720 is an apocalyptic number.

668493018720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

668493018720 is an abundant number, since it is smaller than the sum of its proper divisors (1613159539920).

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

668493018720 is a wasteful number, since it uses less digits than its factorization.

668493018720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85517 (or 85506 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 54.

The spelling of 668493018720 in words is "six hundred sixty-eight billion, four hundred ninety-three million, eighteen thousand, seven hundred twenty".