1666117069 has 2 divisors, whose sum is σ = 1666117070. Its totient is φ = 1666117068.

The previous prime is 1666117043. The next prime is 1666117097. The reversal of 1666117069 is 9607116661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1665456100 + 660969 = 40810^2 + 813^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666117069 - 2²⁵ = 1632562637 is a prime.

It is a super-2 number, since 2×1666117069² = 5551892175226301522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666117099) 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, 833058534 + 833058535.

It is an arithmetic number, because the mean of its divisors is an integer number (833058535).

Almost surely, 2^1666117069 is an apocalyptic number.

It is an amenable number.

1666117069 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666117069 is an equidigital number, since it uses as much as digits as its factorization.

1666117069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 1666117069 is about 40818.0973221438. The cubic root of 1666117069 is about 1185.5007631515.

The spelling of 1666117069 in words is "one billion, six hundred sixty-six million, one hundred seventeen thousand, sixty-nine".