1668459613 has 2 divisors, whose sum is σ = 1668459614. Its totient is φ = 1668459612.

The previous prime is 1668459599. The next prime is 1668459619. The reversal of 1668459613 is 3169548661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1643329444 + 25130169 = 40538^2 + 5013^2 .

It is an emirp because it is prime and its reverse (3169548661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1668459613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668459619) 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, 834229806 + 834229807.

It is an arithmetic number, because the mean of its divisors is an integer number (834229807).

Almost surely, 2^1668459613 is an apocalyptic number.

It is an amenable number.

1668459613 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668459613 is an equidigital number, since it uses as much as digits as its factorization.

1668459613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 933120, while the sum is 49.

The square root of 1668459613 is about 40846.7821621239. The cubic root of 1668459613 is about 1186.0561037191.

The spelling of 1668459613 in words is "one billion, six hundred sixty-eight million, four hundred fifty-nine thousand, six hundred thirteen".