66244765 has 4 divisors (see below), whose sum is σ = 79493724. Its totient is φ = 52995808.

The previous prime is 66244751. The next prime is 66244769. The reversal of 66244765 is 56744266.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23551609 + 42693156 = 4853^2 + 6534^2 .

It is a cyclic number.

It is not a de Polignac number, because 66244765 - 2⁷ = 66244637 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66244769) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6624472 + ... + 6624481.

It is an arithmetic number, because the mean of its divisors is an integer number (19873431).

Almost surely, 2^66244765 is an apocalyptic number.

It is an amenable number.

66244765 is a deficient number, since it is larger than the sum of its proper divisors (13248959).

66244765 is a wasteful number, since it uses less digits than its factorization.

66244765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13248958.

The product of its digits is 241920, while the sum is 40.

The square root of 66244765 is about 8139.0887082031. The cubic root of 66244765 is about 404.6229585508.

The spelling of 66244765 in words is "sixty-six million, two hundred forty-four thousand, seven hundred sixty-five".