55420 has 24 divisors (see below), whose sum is σ = 123984. Its totient is φ = 20736.

The previous prime is 55411. The next prime is 55439. The reversal of 55420 is 2455.

It is a happy number.

55420 is nontrivially palindromic in base 13.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 55394 and 55403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 259 + ... + 421.

It is an arithmetic number, because the mean of its divisors is an integer number (5166).

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).

55420 is an abundant number, since it is smaller than the sum of its proper divisors (68564).

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 sum of its prime factors is 189 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 16.

The square root of 55420 is about 235.4145280139. The cubic root of 55420 is about 38.1260816678.

Adding to 55420 its reverse (2455), we get a palindrome (57875).

The spelling of 55420 in words is "fifty-five thousand, four hundred twenty".