668630442 has 8 divisors (see below), whose sum is σ = 1337260896. Its totient is φ = 222876812.

The previous prime is 668630341. The next prime is 668630491. The reversal of 668630442 is 244036866.

It is a sphenic number, since it is the product of 3 distinct primes.

668630442 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 668630442.

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 3 ways as a sum of consecutive naturals, for example, 55719198 + ... + 55719209.

It is an arithmetic number, because the mean of its divisors is an integer number (167157612).

Almost surely, 2^668630442 is an apocalyptic number.

668630442 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

668630442 is a wasteful number, since it uses less digits than its factorization.

668630442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111438412.

The product of its (nonzero) digits is 165888, while the sum is 39.

The square root of 668630442 is about 25857.8893570222. The cubic root of 668630442 is about 874.4373817742.

It can be divided in two parts, 6686 and 30442, that added together give a triangular number (37128 = T₂₇₂).

The spelling of 668630442 in words is "six hundred sixty-eight million, six hundred thirty thousand, four hundred forty-two".