669443189 has 2 divisors, whose sum is σ = 669443190. Its totient is φ = 669443188.

The previous prime is 669443179. The next prime is 669443213. The reversal of 669443189 is 981344966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 624150289 + 45292900 = 24983^2 + 6730^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669443189 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669443179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334721594 + 334721595.

It is an arithmetic number, because the mean of its divisors is an integer number (334721595).

Almost surely, 2^669443189 is an apocalyptic number.

It is an amenable number.

669443189 is a deficient number, since it is larger than the sum of its proper divisors (1).

669443189 is an equidigital number, since it uses as much as digits as its factorization.

669443189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1119744, while the sum is 50.

The square root of 669443189 is about 25873.6002326696. The cubic root of 669443189 is about 874.7915428316.

The spelling of 669443189 in words is "six hundred sixty-nine million, four hundred forty-three thousand, one hundred eighty-nine".