66157717 has 4 divisors (see below), whose sum is σ = 67565376. Its totient is φ = 64750060.

The previous prime is 66157709. The next prime is 66157769. The reversal of 66157717 is 71775166.

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 66157717 - 2³ = 66157709 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66157717.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66157417) 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, 703759 + ... + 703852.

It is an arithmetic number, because the mean of its divisors is an integer number (16891344).

Almost surely, 2^66157717 is an apocalyptic number.

It is an amenable number.

66157717 is a deficient number, since it is larger than the sum of its proper divisors (1407659).

66157717 is a wasteful number, since it uses less digits than its factorization.

66157717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407658.

The product of its digits is 61740, while the sum is 40.

The square root of 66157717 is about 8133.7394229223. The cubic root of 66157717 is about 404.4456511663.

The spelling of 66157717 in words is "sixty-six million, one hundred fifty-seven thousand, seven hundred seventeen".