66605071 has 4 divisors (see below), whose sum is σ = 71728552. Its totient is φ = 61481592.

The previous prime is 66605059. The next prime is 66605117. The reversal of 66605071 is 17050666.

66605071 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 66605071 - 2⁷ = 66604943 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 (66605971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2561721 + ... + 2561746.

It is an arithmetic number, because the mean of its divisors is an integer number (17932138).

Almost surely, 2^66605071 is an apocalyptic number.

66605071 is a deficient number, since it is larger than the sum of its proper divisors (5123481).

66605071 is a wasteful number, since it uses less digits than its factorization.

66605071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5123480.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 66605071 is about 8161.1929887731. The cubic root of 66605071 is about 405.3552154628.

The spelling of 66605071 in words is "sixty-six million, six hundred five thousand, seventy-one".