6665166449 has 2 divisors, whose sum is σ = 6665166450. Its totient is φ = 6665166448.

The previous prime is 6665166401. The next prime is 6665166451. The reversal of 6665166449 is 9446615666.

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., 4097920225 + 2567246224 = 64015^2 + 50668^2 .

It is a cyclic number.

It is not a de Polignac number, because 6665166449 - 2²⁸ = 6396730993 is a prime.

Together with 6665166451, it forms a pair of twin primes.

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 6665166449.

It is not a weakly prime, because it can be changed into another prime (6665165449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3332583224 + 3332583225.

It is an arithmetic number, because the mean of its divisors is an integer number (3332583225).

Almost surely, 2^6665166449 is an apocalyptic number.

It is an amenable number.

6665166449 is a deficient number, since it is larger than the sum of its proper divisors (1).

6665166449 is an equidigital number, since it uses as much as digits as its factorization.

6665166449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5598720, while the sum is 53.

The square root of 6665166449 is about 81640.4706564091. The cubic root of 6665166449 is about 1881.9308712835.

The spelling of 6665166449 in words is "six billion, six hundred sixty-five million, one hundred sixty-six thousand, four hundred forty-nine".