668388340 has 24 divisors (see below), whose sum is σ = 1416737952. Its totient is φ = 264855840.

The previous prime is 668388319. The next prime is 668388359. The reversal of 668388340 is 43883866.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 154026 + ... + 158305.

It is an arithmetic number, because the mean of its divisors is an integer number (59030748).

Almost surely, 2^668388340 is an apocalyptic number.

It is an amenable number.

668388340 is an abundant number, since it is smaller than the sum of its proper divisors (748349612).

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

668388340 is a wasteful number, since it uses less digits than its factorization.

668388340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312447 (or 312445 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 46.

The square root of 668388340 is about 25853.2075379439. The cubic root of 668388340 is about 874.3318284010.

The spelling of 668388340 in words is "six hundred sixty-eight million, three hundred eighty-eight thousand, three hundred forty".