1666344269 has 2 divisors, whose sum is σ = 1666344270. Its totient is φ = 1666344268.

The previous prime is 1666344193. The next prime is 1666344283. The reversal of 1666344269 is 9624436661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1596002500 + 70341769 = 39950^2 + 8387^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666344269 - 2¹² = 1666340173 is a prime.

It is a super-2 number, since 2×1666344269² = 5553406445658288722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666344569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833172134 + 833172135.

It is an arithmetic number, because the mean of its divisors is an integer number (833172135).

Almost surely, 2^1666344269 is an apocalyptic number.

It is an amenable number.

1666344269 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666344269 is an equidigital number, since it uses as much as digits as its factorization.

1666344269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1119744, while the sum is 47.

The square root of 1666344269 is about 40820.8803065294. The cubic root of 1666344269 is about 1185.5546476266.

The spelling of 1666344269 in words is "one billion, six hundred sixty-six million, three hundred forty-four thousand, two hundred sixty-nine".