667272209 has 2 divisors, whose sum is σ = 667272210. Its totient is φ = 667272208.

The previous prime is 667272181. The next prime is 667272233. The reversal of 667272209 is 902272766.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 429649984 + 237622225 = 20728^2 + 15415^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667272209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (667272239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333636104 + 333636105.

It is an arithmetic number, because the mean of its divisors is an integer number (333636105).

Almost surely, 2^667272209 is an apocalyptic number.

It is an amenable number.

667272209 is a deficient number, since it is larger than the sum of its proper divisors (1).

667272209 is an equidigital number, since it uses as much as digits as its factorization.

667272209 is an odious number, because the sum of its binary digits is odd.

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

The square root of 667272209 is about 25831.6125900030. The cubic root of 667272209 is about 873.8448796717.

The spelling of 667272209 in words is "six hundred sixty-seven million, two hundred seventy-two thousand, two hundred nine".