220181 has 4 divisors (see below), whose sum is σ = 237132. Its totient is φ = 203232.

The previous prime is 220177. The next prime is 220189. The reversal of 220181 is 181022.

220181 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: 181022 = 2 ⋅90511.

It can be written as a sum of positive squares in 2 ways, for example, as 52900 + 167281 = 230^2 + 409^2 .

It is a cyclic number.

It is not a de Polignac number, because 220181 - 2² = 220177 is a prime.

It is a super-2 number, since 2×220181² = 96959345522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220189) 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, 8456 + ... + 8481.

It is an arithmetic number, because the mean of its divisors is an integer number (59283).

2²²⁰¹⁸¹ is an apocalyptic number.

It is an amenable number.

220181 is a deficient number, since it is larger than the sum of its proper divisors (16951).

220181 is a wasteful number, since it uses less digits than its factorization.

220181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16950.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 220181 is about 469.2344829613. The cubic root of 220181 is about 60.3846583259.

The spelling of 220181 in words is "two hundred twenty thousand, one hundred eighty-one".