660667211 has 2 divisors, whose sum is σ = 660667212. Its totient is φ = 660667210.

The previous prime is 660667181. The next prime is 660667213. The reversal of 660667211 is 112766066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 660667211 - 2¹⁰ = 660666187 is a prime.

Together with 660667213, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (660667213) 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 as a sum of consecutive naturals, namely, 330333605 + 330333606.

It is an arithmetic number, because the mean of its divisors is an integer number (330333606).

Almost surely, 2^660667211 is an apocalyptic number.

660667211 is a deficient number, since it is larger than the sum of its proper divisors (1).

660667211 is an equidigital number, since it uses as much as digits as its factorization.

660667211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 660667211 is about 25703.4474536005. The cubic root of 660667211 is about 870.9520607661.

The spelling of 660667211 in words is "six hundred sixty million, six hundred sixty-seven thousand, two hundred eleven".