55181 has 4 divisors (see below), whose sum is σ = 63072. Its totient is φ = 47292.

The previous prime is 55171. The next prime is 55201. The reversal of 55181 is 18155.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18155 = 5 ⋅3631.

It is not a de Polignac number, because 55181 - 2⁶ = 55117 is a prime.

It is a super-2 number, since 2×55181² = 6089885522, 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 (55171) 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, 3935 + ... + 3948.

It is an arithmetic number, because the mean of its divisors is an integer number (15768).

2⁵⁵¹⁸¹ is an apocalyptic number.

It is an amenable number.

55181 is a deficient number, since it is larger than the sum of its proper divisors (7891).

55181 is an equidigital number, since it uses as much as digits as its factorization.

55181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7890.

The product of its digits is 200, while the sum is 20.

The square root of 55181 is about 234.9063643242. The cubic root of 55181 is about 38.0711961646.

The spelling of 55181 in words is "fifty-five thousand, one hundred eighty-one".