66723165 has 12 divisors (see below), whose sum is σ = 115653564. Its totient is φ = 35585664.

The previous prime is 66723157. The next prime is 66723179. The reversal of 66723165 is 56132766.

It can be written as a sum of positive squares in 2 ways, for example, as 15657849 + 51065316 = 3957^2 + 7146^2 .

It is not a de Polignac number, because 66723165 - 2³ = 66723157 is a prime.

It is a Curzon number.

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 11 ways as a sum of consecutive naturals, for example, 741324 + ... + 741413.

It is an arithmetic number, because the mean of its divisors is an integer number (9637797).

Almost surely, 2^66723165 is an apocalyptic number.

It is an amenable number.

66723165 is a deficient number, since it is larger than the sum of its proper divisors (48930399).

66723165 is a wasteful number, since it uses less digits than its factorization.

66723165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1482748 (or 1482745 counting only the distinct ones).

The product of its digits is 45360, while the sum is 36.

The square root of 66723165 is about 8168.4248787633. The cubic root of 66723165 is about 405.5946454541.

It can be divided in two parts, 667 and 23165, that added together give a palindrome (23832).

The spelling of 66723165 in words is "sixty-six million, seven hundred twenty-three thousand, one hundred sixty-five".