55220 has 24 divisors (see below), whose sum is σ = 127008.
Its totient is φ = 20000.
The previous prime is 55219. The next prime is 55229. The reversal of 55220 is 2255.
Adding to 55220 its reverse (2255), we get a palindrome (57475).
It can be divided in two parts, 55 and 220, that multiplied together give a square (12100 = 1102).
It is a nialpdrome in base 10.
It is a junction number, because it is equal to n+sod(n) for n = 55195 and 55204.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (55229) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95 + ... + 345.
It is an arithmetic number, because the mean of its divisors is an integer number (5292).
255220 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 55220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63504).
55220 is an abundant number, since it is smaller than the sum of its proper divisors (71788).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
55220 is a wasteful number, since it uses less digits than its factorization.
55220 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 271 (or 269 counting only the distinct ones).
The product of its (nonzero) digits is 100, while the sum is 14.
The square root of 55220 is about 234.9893614613.
The cubic root of 55220 is about 38.0801631822.
The spelling of 55220 in words is "fifty-five thousand, two hundred twenty".