66204565 has 16 divisors (see below), whose sum is σ = 91464192. Its totient is φ = 45062784.

The previous prime is 66204539. The next prime is 66204577. The reversal of 66204565 is 56540266.

It is a cyclic number.

It is not a de Polignac number, because 66204565 - 2⁵ = 66204533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66204565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2109 + ... + 11698.

It is an arithmetic number, because the mean of its divisors is an integer number (5716512).

Almost surely, 2^66204565 is an apocalyptic number.

It is an amenable number.

66204565 is a deficient number, since it is larger than the sum of its proper divisors (25259627).

66204565 is a wasteful number, since it uses less digits than its factorization.

66204565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13956.

The product of its (nonzero) digits is 43200, while the sum is 34.

The square root of 66204565 is about 8136.6187694890. The cubic root of 66204565 is about 404.5410948025.

The spelling of 66204565 in words is "sixty-six million, two hundred four thousand, five hundred sixty-five".