668198380 has 24 divisors (see below), whose sum is σ = 1415639232. Its totient is φ = 264913152.

The previous prime is 668198357. The next prime is 668198393. The reversal of 668198380 is 83891866.

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, 145572 + ... + 150091.

It is an arithmetic number, because the mean of its divisors is an integer number (58984968).

Almost surely, 2^668198380 is an apocalyptic number.

It is an amenable number.

668198380 is an abundant number, since it is smaller than the sum of its proper divisors (747440852).

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

668198380 is a wasteful number, since it uses less digits than its factorization.

668198380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295785 (or 295783 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 49.

The square root of 668198380 is about 25849.5334580723. The cubic root of 668198380 is about 874.2489904253.

The spelling of 668198380 in words is "six hundred sixty-eight million, one hundred ninety-eight thousand, three hundred eighty".