667308689 has 2 divisors, whose sum is σ = 667308690. Its totient is φ = 667308688.

The previous prime is 667308641. The next prime is 667308721. The reversal of 667308689 is 986803766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 652036225 + 15272464 = 25535^2 + 3908^2 .

It is a cyclic number.

It is not a de Polignac number, because 667308689 - 2¹² = 667304593 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 667308689.

It is not a weakly prime, because it can be changed into another prime (667308619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333654344 + 333654345.

It is an arithmetic number, because the mean of its divisors is an integer number (333654345).

Almost surely, 2^667308689 is an apocalyptic number.

It is an amenable number.

667308689 is a deficient number, since it is larger than the sum of its proper divisors (1).

667308689 is an equidigital number, since it uses as much as digits as its factorization.

667308689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2612736, while the sum is 53.

The square root of 667308689 is about 25832.3186919022. The cubic root of 667308689 is about 873.8608038477.

The spelling of 667308689 in words is "six hundred sixty-seven million, three hundred eight thousand, six hundred eighty-nine".