66605317 has 4 divisors (see below), whose sum is σ = 70110880. Its totient is φ = 63099756.

The previous prime is 66605311. The next prime is 66605327. The reversal of 66605317 is 71350666.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66605317 - 2¹¹ = 66603269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66605311) 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, 1752753 + ... + 1752790.

It is an arithmetic number, because the mean of its divisors is an integer number (17527720).

Almost surely, 2^66605317 is an apocalyptic number.

It is an amenable number.

66605317 is a deficient number, since it is larger than the sum of its proper divisors (3505563).

66605317 is a wasteful number, since it uses less digits than its factorization.

66605317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3505562.

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 66605317 is about 8161.2080600852. The cubic root of 66605317 is about 405.3557145102.

The spelling of 66605317 in words is "sixty-six million, six hundred five thousand, three hundred seventeen".