6665413309 has 2 divisors, whose sum is σ = 6665413310. Its totient is φ = 6665413308.

The previous prime is 6665413303. The next prime is 6665413319. The reversal of 6665413309 is 9033145666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6489108025 + 176305284 = 80555^2 + 13278^2 .

It is a cyclic number.

It is not a de Polignac number, because 6665413309 - 2³ = 6665413301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6665413301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3332706654 + 3332706655.

It is an arithmetic number, because the mean of its divisors is an integer number (3332706655).

Almost surely, 2^6665413309 is an apocalyptic number.

It is an amenable number.

6665413309 is a deficient number, since it is larger than the sum of its proper divisors (1).

6665413309 is an equidigital number, since it uses as much as digits as its factorization.

6665413309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 349920, while the sum is 43.

The square root of 6665413309 is about 81641.9825151251. The cubic root of 6665413309 is about 1881.9541048978.

The spelling of 6665413309 in words is "six billion, six hundred sixty-five million, four hundred thirteen thousand, three hundred nine".