66575717 has 4 divisors (see below), whose sum is σ = 71696940. Its totient is φ = 61454496.

The previous prime is 66575687. The next prime is 66575737. The reversal of 66575717 is 71757566.

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 3865156 + 62710561 = 1966^2 + 7919^2 .

It is a cyclic number.

It is not a de Polignac number, because 66575717 - 2¹⁴ = 66559333 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 (66575737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2560592 + ... + 2560617.

It is an arithmetic number, because the mean of its divisors is an integer number (17924235).

Almost surely, 2^66575717 is an apocalyptic number.

It is an amenable number.

66575717 is a deficient number, since it is larger than the sum of its proper divisors (5121223).

66575717 is a wasteful number, since it uses less digits than its factorization.

66575717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5121222.

The product of its digits is 308700, while the sum is 44.

The square root of 66575717 is about 8159.3944015472. The cubic root of 66575717 is about 405.2956577082.

The spelling of 66575717 in words is "sixty-six million, five hundred seventy-five thousand, seven hundred seventeen".