55278 has 24 divisors (see below), whose sum is σ = 124488. Its totient is φ = 17712.

The previous prime is 55259. The next prime is 55291. The reversal of 55278 is 87255.

It is a happy number.

55278 is a nontrivial binomial coefficient, being equal to C(333, 2).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 625 + ... + 707.

It is an arithmetic number, because the mean of its divisors is an integer number (5187).

2⁵⁵²⁷⁸ is an apocalyptic number.

55278 is the 332-nd triangular number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62244).

55278 is an abundant number, since it is smaller than the sum of its proper divisors (69210).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55278 is a wasteful number, since it uses less digits than its factorization.

55278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128 (or 125 counting only the distinct ones).

The product of its digits is 2800, while the sum is 27.

The square root of 55278 is about 235.1127389148. The cubic root of 55278 is about 38.0934909417.

It can be divided in two parts, 552 and 78, that added together give a triangular number (630 = T₃₅).

The spelling of 55278 in words is "fifty-five thousand, two hundred seventy-eight".