668740567 has 4 divisors (see below), whose sum is σ = 729535176. Its totient is φ = 607945960.

The previous prime is 668740559. The next prime is 668740607. The reversal of 668740567 is 765047866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 668740567 - 2³ = 668740559 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 668740567.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668740507) by changing a digit.

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, 30397288 + ... + 30397309.

It is an arithmetic number, because the mean of its divisors is an integer number (182383794).

Almost surely, 2^668740567 is an apocalyptic number.

668740567 is a deficient number, since it is larger than the sum of its proper divisors (60794609).

668740567 is a wasteful number, since it uses less digits than its factorization.

668740567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60794608.

The product of its (nonzero) digits is 1693440, while the sum is 49.

The square root of 668740567 is about 25860.0186968223. The cubic root of 668740567 is about 874.4853864338.

The spelling of 668740567 in words is "six hundred sixty-eight million, seven hundred forty thousand, five hundred sixty-seven".