668186320 has 40 divisors (see below), whose sum is σ = 1556166024. Its totient is φ = 266821632.

The previous prime is 668186291. The next prime is 668186327. The reversal of 668186320 is 23681866.

It can be written as a sum of positive squares in 4 ways, for example, as 70090384 + 598095936 = 8372^2 + 24456^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668186327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42592 + ... + 56128.

Almost surely, 2^668186320 is an apocalyptic number.

It is an amenable number.

668186320 is an abundant number, since it is smaller than the sum of its proper divisors (887979704).

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

668186320 is a wasteful number, since it uses less digits than its factorization.

668186320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14167 (or 14161 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 668186320 is about 25849.3001839508. The cubic root of 668186320 is about 874.2437307567.

The spelling of 668186320 in words is "six hundred sixty-eight million, one hundred eighty-six thousand, three hundred twenty".