66064209 has 4 divisors (see below), whose sum is σ = 88085616. Its totient is φ = 44042804.

The previous prime is 66064189. The next prime is 66064213. The reversal of 66064209 is 90246066.

66064209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66064209 - 2⁵ = 66064177 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66064209.

It is not an unprimeable number, because it can be changed into a prime (66064249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11010699 + ... + 11010704.

It is an arithmetic number, because the mean of its divisors is an integer number (22021404).

Almost surely, 2^66064209 is an apocalyptic number.

It is an amenable number.

66064209 is a deficient number, since it is larger than the sum of its proper divisors (22021407).

66064209 is a wasteful number, since it uses less digits than its factorization.

66064209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22021406.

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 66064209 is about 8127.9892347370. The cubic root of 66064209 is about 404.2550121018.

The spelling of 66064209 in words is "sixty-six million, sixty-four thousand, two hundred nine".