66505307 has 4 divisors (see below), whose sum is σ = 72551256. Its totient is φ = 60459360.

The previous prime is 66505303. The next prime is 66505319. The reversal of 66505307 is 70350566.

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

It is a cyclic number.

It is not a de Polignac number, because 66505307 - 2² = 66505303 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66505303) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3022958 + ... + 3022979.

It is an arithmetic number, because the mean of its divisors is an integer number (18137814).

Almost surely, 2^66505307 is an apocalyptic number.

66505307 is a deficient number, since it is larger than the sum of its proper divisors (6045949).

66505307 is a wasteful number, since it uses less digits than its factorization.

66505307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6045948.

The product of its (nonzero) digits is 18900, while the sum is 32.

The square root of 66505307 is about 8155.0786017058. The cubic root of 66505307 is about 405.1527280506.

The spelling of 66505307 in words is "sixty-six million, five hundred five thousand, three hundred seven".