665161610161 has 8 divisors (see below), whose sum is σ = 695461576320. Its totient is φ = 634976635392.

The previous prime is 665161610159. The next prime is 665161610177. The reversal of 665161610161 is 161016161566.

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 665161610161 - 2¹ = 665161610159 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665161610131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28736016 + ... + 28759153.

It is an arithmetic number, because the mean of its divisors is an integer number (86932697040).

Almost surely, 2^665161610161 is an apocalyptic number.

It is an amenable number.

665161610161 is a deficient number, since it is larger than the sum of its proper divisors (30299966159).

665161610161 is a wasteful number, since it uses less digits than its factorization.

665161610161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57495695.

The product of its (nonzero) digits is 38880, while the sum is 40.

The spelling of 665161610161 in words is "six hundred sixty-five billion, one hundred sixty-one million, six hundred ten thousand, one hundred sixty-one".