6664920805 has 16 divisors (see below), whose sum is σ = 8584383024. Its totient is φ = 4949544960.

The previous prime is 6664920791. The next prime is 6664920859. The reversal of 6664920805 is 5080294666.

It can be written as a sum of positive squares in 8 ways, for example, as 23648769 + 6641272036 = 4863^2 + 81494^2 .

It is not a de Polignac number, because 6664920805 - 2⁹ = 6664920293 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 530856 + ... + 543265.

It is an arithmetic number, because the mean of its divisors is an integer number (536523939).

Almost surely, 2^6664920805 is an apocalyptic number.

It is an amenable number.

6664920805 is a deficient number, since it is larger than the sum of its proper divisors (1919462219).

6664920805 is a wasteful number, since it uses less digits than its factorization.

6664920805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1074216.

The product of its (nonzero) digits is 622080, while the sum is 46.

The square root of 6664920805 is about 81638.9662171196. The cubic root of 6664920805 is about 1881.9077515454.

The spelling of 6664920805 in words is "six billion, six hundred sixty-four million, nine hundred twenty thousand, eight hundred five".