666716207 has 4 divisors (see below), whose sum is σ = 666767976. Its totient is φ = 666664440.

The previous prime is 666716201. The next prime is 666716233. The reversal of 666716207 is 702617666.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 666716207 - 2¹⁰ = 666715183 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 (666716201) 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, 10232 + ... + 37922.

It is an arithmetic number, because the mean of its divisors is an integer number (166691994).

Almost surely, 2^666716207 is an apocalyptic number.

666716207 is a deficient number, since it is larger than the sum of its proper divisors (51769).

666716207 is a wasteful number, since it uses less digits than its factorization.

666716207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51768.

The product of its (nonzero) digits is 127008, while the sum is 41.

The square root of 666716207 is about 25820.8483013243. The cubic root of 666716207 is about 873.6021029340.

The spelling of 666716207 in words is "six hundred sixty-six million, seven hundred sixteen thousand, two hundred seven".