668281007 has 4 divisors (see below), whose sum is σ = 668403000. Its totient is φ = 668159016.

The previous prime is 668280989. The next prime is 668281027. The reversal of 668281007 is 700182866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 700182866 = 2 ⋅350091433.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668281007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668281027) 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 3 ways as a sum of consecutive naturals, for example, 52373 + ... + 63870.

It is an arithmetic number, because the mean of its divisors is an integer number (167100750).

Almost surely, 2^668281007 is an apocalyptic number.

668281007 is a deficient number, since it is larger than the sum of its proper divisors (121993).

668281007 is a wasteful number, since it uses less digits than its factorization.

668281007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121992.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 668281007 is about 25851.1316386730. The cubic root of 668281007 is about 874.2850244317.

The spelling of 668281007 in words is "six hundred sixty-eight million, two hundred eighty-one thousand, seven".