36181 has 4 divisors (see below), whose sum is σ = 36652. Its totient is φ = 35712.

The previous prime is 36161. The next prime is 36187. The reversal of 36181 is 18163.

36181 = 134² + 135².

36181 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 an emirpimes, since its reverse is a distinct semiprime: 18163 = 41 ⋅443.

It can be written as a sum of positive squares in 2 ways, for example, as 17956 + 18225 = 134^2 + 135^2 .

It is a cyclic number.

It is not a de Polignac number, because 36181 - 2¹⁵ = 3413 is a prime.

It is a super-2 number, since 2×36181² = 2618129522, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (36187) 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, 90 + ... + 283.

It is an arithmetic number, because the mean of its divisors is an integer number (9163).

2³⁶¹⁸¹ is an apocalyptic number.

36181 is the 135-th centered square number.

It is an amenable number.

36181 is a deficient number, since it is larger than the sum of its proper divisors (471).

36181 is an equidigital number, since it uses as much as digits as its factorization.

36181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470.

The product of its digits is 144, while the sum is 19.

The square root of 36181 is about 190.2130384595. The cubic root of 36181 is about 33.0745178598.

It can be divided in two parts, 361 and 81, that multiplied together give a square (29241 = 171²).

The spelling of 36181 in words is "thirty-six thousand, one hundred eighty-one".