666705007 has 4 divisors (see below), whose sum is σ = 676655896. Its totient is φ = 656754120.

The previous prime is 666705001. The next prime is 666705019. The reversal of 666705007 is 700507666.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666705007 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 (666705001) 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, 4975344 + ... + 4975477.

It is an arithmetic number, because the mean of its divisors is an integer number (169163974).

Almost surely, 2^666705007 is an apocalyptic number.

666705007 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

666705007 is a deficient number, since it is larger than the sum of its proper divisors (9950889).

666705007 is an equidigital number, since it uses as much as digits as its factorization.

666705007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9950888.

The product of its (nonzero) digits is 52920, while the sum is 37.

The square root of 666705007 is about 25820.6314214041. The cubic root of 666705007 is about 873.5972110984.

The spelling of 666705007 in words is "six hundred sixty-six million, seven hundred five thousand, seven".