66388365 has 12 divisors (see below), whose sum is σ = 115073244. Its totient is φ = 35407104.

The previous prime is 66388363. The next prime is 66388381. The reversal of 66388365 is 56388366.

66388365 is a `hidden beast` number, since 6 + 638 + 8 + 3 + 6 + 5 = 666.

66388365 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 39576681 + 26811684 = 6291^2 + 5178^2 .

It is not a de Polignac number, because 66388365 - 2¹ = 66388363 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 1475297 = 66388365 / (6 + 6 + 3 + 8 + 8 + 3 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 66388365.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66388363) 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 11 ways as a sum of consecutive naturals, for example, 737604 + ... + 737693.

It is an arithmetic number, because the mean of its divisors is an integer number (9589437).

Almost surely, 2^66388365 is an apocalyptic number.

It is an amenable number.

66388365 is a deficient number, since it is larger than the sum of its proper divisors (48684879).

66388365 is a wasteful number, since it uses less digits than its factorization.

66388365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475308 (or 1475305 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The square root of 66388365 is about 8147.9055590992. The cubic root of 66388365 is about 404.9151170988.

Subtracting from 66388365 its reverse (56388366), we obtain a palindrome (9999999).

The spelling of 66388365 in words is "sixty-six million, three hundred eighty-eight thousand, three hundred sixty-five".