66161605 has 8 divisors (see below), whose sum is σ = 79437600. Its totient is φ = 52900176.

The previous prime is 66161581. The next prime is 66161609. The reversal of 66161605 is 50616166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66161605 - 2¹¹ = 66159557 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66161609) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15826 + ... + 19564.

It is an arithmetic number, because the mean of its divisors is an integer number (9929700).

Almost surely, 2^66161605 is an apocalyptic number.

It is an amenable number.

66161605 is a deficient number, since it is larger than the sum of its proper divisors (13275995).

66161605 is a wasteful number, since it uses less digits than its factorization.

66161605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7283.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 66161605 is about 8133.9784238711. The cubic root of 66161605 is about 404.4535739200.

It can be divided in two parts, 66161 and 605, that added together give a palindrome (66766).

The spelling of 66161605 in words is "sixty-six million, one hundred sixty-one thousand, six hundred five".