660161309 has 4 divisors (see below), whose sum is σ = 660234204. Its totient is φ = 660088416.

The previous prime is 660161291. The next prime is 660161317. The reversal of 660161309 is 903161066.

660161309 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, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 96098809 + 564062500 = 9803^2 + 23750^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660161309 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 (660161329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20552 + ... + 41745.

It is an arithmetic number, because the mean of its divisors is an integer number (165058551).

Almost surely, 2^660161309 is an apocalyptic number.

It is an amenable number.

660161309 is a deficient number, since it is larger than the sum of its proper divisors (72895).

660161309 is a wasteful number, since it uses less digits than its factorization.

660161309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72894.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 660161309 is about 25693.6044376806. The cubic root of 660161309 is about 870.7296952057.

The spelling of 660161309 in words is "six hundred sixty million, one hundred sixty-one thousand, three hundred nine".