55111 has 4 divisors (see below), whose sum is σ = 62992.
Its totient is φ = 47232.
The previous prime is 55109. The next prime is 55117. The reversal of 55111 is 11155.
Adding to 55111 its reverse (11155), we get a palindrome (66266).
Subtracting from 55111 its reverse (11155), we obtain a triangular number (43956 = T296).
It can be divided in two parts, 55 and 111, that multiplied together give a triangular number (6105 = T110).
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 55111 - 21 = 55109 is a prime.
It is a Duffinian number.
55111 is a modest number, since divided by 111 gives 55 as remainder.
It is a nialpdrome in base 10.
It is a zygodrome in base 10.
It is a junction number, because it is equal to n+sod(n) for n = 55091 and 55100.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (55117) 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, 3930 + ... + 3943.
It is an arithmetic number, because the mean of its divisors is an integer number (15748).
255111 is an apocalyptic number.
55111 is a deficient number, since it is larger than the sum of its proper divisors (7881).
55111 is an equidigital number, since it uses as much as digits as its factorization.
55111 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 7880.
The product of its digits is 25, while the sum is 13.
The square root of 55111 is about 234.7573215046.
The cubic root of 55111 is about 38.0550909145.
The spelling of 55111 in words is "fifty-five thousand, one hundred eleven".