66505071 has 16 divisors (see below), whose sum is σ = 95295744. Its totient is φ = 41103744.

The previous prime is 66505069. The next prime is 66505079. The reversal of 66505071 is 17050566.

It is not a de Polignac number, because 66505071 - 2¹ = 66505069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66505079) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6315 + ... + 13148.

It is an arithmetic number, because the mean of its divisors is an integer number (5955984).

Almost surely, 2^66505071 is an apocalyptic number.

66505071 is a deficient number, since it is larger than the sum of its proper divisors (28790673).

66505071 is a wasteful number, since it uses less digits than its factorization.

66505071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19550.

The product of its (nonzero) digits is 6300, while the sum is 30.

The square root of 66505071 is about 8155.0641321819. The cubic root of 66505071 is about 405.1522488099.

The spelling of 66505071 in words is "sixty-six million, five hundred five thousand, seventy-one".