181365 has 16 divisors (see below), whose sum is σ = 295488. Its totient is φ = 94976.

The previous prime is 181361. The next prime is 181387. The reversal of 181365 is 563181.

181365 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 181365 - 2² = 181361 is a prime.

181365 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 181365.

It is not an unprimeable number, because it can be changed into a prime (181361) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1549 + ... + 1661.

It is an arithmetic number, because the mean of its divisors is an integer number (18468).

2¹⁸¹³⁶⁵ is an apocalyptic number.

181365 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

181365 is a deficient number, since it is larger than the sum of its proper divisors (114123).

181365 is a wasteful number, since it uses less digits than its factorization.

181365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228.

The product of its digits is 720, while the sum is 24.

The square root of 181365 is about 425.8696983820. The cubic root of 181365 is about 56.6045262688.

The spelling of 181365 in words is "one hundred eighty-one thousand, three hundred sixty-five".