66660085 has 4 divisors (see below), whose sum is σ = 79992108. Its totient is φ = 53328064.

The previous prime is 66660071. The next prime is 66660103. The reversal of 66660085 is 58006666.

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 43533604 + 23126481 = 6598^2 + 4809^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66660085 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6666004 + ... + 6666013.

It is an arithmetic number, because the mean of its divisors is an integer number (19998027).

Almost surely, 2^66660085 is an apocalyptic number.

It is an amenable number.

66660085 is a deficient number, since it is larger than the sum of its proper divisors (13332023).

66660085 is a wasteful number, since it uses less digits than its factorization.

66660085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13332022.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 66660085 is about 8164.5627562044. The cubic root of 66660085 is about 405.4667889237.

The spelling of 66660085 in words is "sixty-six million, six hundred sixty thousand, eighty-five".