66616605 has 48 divisors (see below), whose sum is σ = 128157120. Its totient is φ = 31737600.

The previous prime is 66616597. The next prime is 66616609. The reversal of 66616605 is 50661666.

It is not a de Polignac number, because 66616605 - 2³ = 66616597 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66616605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66616609) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 28065 + ... + 30345.

It is an arithmetic number, because the mean of its divisors is an integer number (2669940).

Almost surely, 2^66616605 is an apocalyptic number.

It is an amenable number.

66616605 is a deficient number, since it is larger than the sum of its proper divisors (61540515).

66616605 is a wasteful number, since it uses less digits than its factorization.

66616605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2362 (or 2359 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 66616605 is about 8161.8995950698. The cubic root of 66616605 is about 405.3786125663.

It can be divided in two parts, 666 and 16605, that added together give a palindrome (17271).

The spelling of 66616605 in words is "sixty-six million, six hundred sixteen thousand, six hundred five".