Adding to 55420 its reverse (2455), we get a palindrome (57875).
It is a happy number.
55420 is nontrivially palindromic in base 13.
It is a nialpdrome in base 10.
It is a congruent number.
It is an unprimeable number.
255420 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 55420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61992).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
55420 is a wasteful number, since it uses less digits than its factorization.
55420 is an odious number, because the sum of its binary digits is odd.
The square root of 55420 is about 235.4145280139. The cubic root of 55420 is about 38.1260816678.
The spelling of 55420 in words is "fifty-five thousand, four hundred twenty".