666321071 has 8 divisors (see below), whose sum is σ = 720713280. Its totient is φ = 612376992.

The previous prime is 666321067. The next prime is 666321083. The reversal of 666321071 is 170123666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666321071 - 2² = 666321067 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 (666321871) 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, 108935 + ... + 114888.

It is an arithmetic number, because the mean of its divisors is an integer number (90089160).

Almost surely, 2^666321071 is an apocalyptic number.

666321071 is a deficient number, since it is larger than the sum of its proper divisors (54392209).

666321071 is a wasteful number, since it uses less digits than its factorization.

666321071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224065.

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 666321071 is about 25813.1956758554. The cubic root of 666321071 is about 873.4294858329.

The spelling of 666321071 in words is "six hundred sixty-six million, three hundred twenty-one thousand, seventy-one".