668243730 has 64 divisors (see below), whose sum is σ = 1999531008. Its totient is φ = 138855360.

The previous prime is 668243687. The next prime is 668243731. The reversal of 668243730 is 37342866.

668243730 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (668243731) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 142332 + ... + 146951.

It is an arithmetic number, because the mean of its divisors is an integer number (31242672).

Almost surely, 2^668243730 is an apocalyptic number.

668243730 is an abundant number, since it is smaller than the sum of its proper divisors (1331287278).

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

668243730 is a wasteful number, since it uses less digits than its factorization.

668243730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289311.

The product of its (nonzero) digits is 145152, while the sum is 39.

The square root of 668243730 is about 25850.4106350363. The cubic root of 668243730 is about 874.2687681321.

The spelling of 668243730 in words is "six hundred sixty-eight million, two hundred forty-three thousand, seven hundred thirty".