161666065 has 16 divisors (see below), whose sum is σ = 212334336. Its totient is φ = 117187200.

The previous prime is 161666051. The next prime is 161666081. The reversal of 161666065 is 560666161.

It is not a de Polignac number, because 161666065 - 2¹¹ = 161664017 is a prime.

It is a super-2 number, since 2×161666065² = 52271833145168450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12520 + ... + 21910.

It is an arithmetic number, because the mean of its divisors is an integer number (13270896).

Almost surely, 2^161666065 is an apocalyptic number.

It is an amenable number.

161666065 is a deficient number, since it is larger than the sum of its proper divisors (50668271).

161666065 is a wasteful number, since it uses less digits than its factorization.

161666065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9720.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 161666065 is about 12714.7970884320. The cubic root of 161666065 is about 544.7613521822.

The spelling of 161666065 in words is "one hundred sixty-one million, six hundred sixty-six thousand, sixty-five".