161766165 has 16 divisors (see below), whose sum is σ = 282355776. Its totient is φ = 78432000.

The previous prime is 161766161. The next prime is 161766191. The reversal of 161766165 is 561667161.

It is not a de Polignac number, because 161766165 - 2² = 161766161 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161766161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 490036 + ... + 490365.

It is an arithmetic number, because the mean of its divisors is an integer number (17647236).

Almost surely, 2^161766165 is an apocalyptic number.

161766165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161766165 is a deficient number, since it is larger than the sum of its proper divisors (120589611).

161766165 is a wasteful number, since it uses less digits than its factorization.

161766165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980420.

The product of its digits is 45360, while the sum is 39.

The square root of 161766165 is about 12718.7328378263. The cubic root of 161766165 is about 544.8737636532.

The spelling of 161766165 in words is "one hundred sixty-one million, seven hundred sixty-six thousand, one hundred sixty-five".