667256325161 has 2 divisors, whose sum is σ = 667256325162. Its totient is φ = 667256325160.

The previous prime is 667256325013. The next prime is 667256325191. The reversal of 667256325161 is 161523652766.

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., 660552809536 + 6703515625 = 812744^2 + 81875^2 .

It is a cyclic number.

It is not a de Polignac number, because 667256325161 - 2³⁸ = 392378418217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (667256325191) 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 as a sum of consecutive naturals, namely, 333628162580 + 333628162581.

It is an arithmetic number, because the mean of its divisors is an integer number (333628162581).

Almost surely, 2^667256325161 is an apocalyptic number.

It is an amenable number.

667256325161 is a deficient number, since it is larger than the sum of its proper divisors (1).

667256325161 is an equidigital number, since it uses as much as digits as its factorization.

667256325161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2721600, while the sum is 50.

The spelling of 667256325161 in words is "six hundred sixty-seven billion, two hundred fifty-six million, three hundred twenty-five thousand, one hundred sixty-one".