55290 has 32 divisors (see below), whose sum is σ = 141120. Its totient is φ = 13824.

The previous prime is 55259. The next prime is 55291. The reversal of 55290 is 9255.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55291) by changing a digit.

55290 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 522 + ... + 618.

It is an arithmetic number, because the mean of its divisors is an integer number (4410).

2⁵⁵²⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70560).

55290 is an abundant number, since it is smaller than the sum of its proper divisors (85830).

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

55290 is a wasteful number, since it uses less digits than its factorization.

55290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 55290 is about 235.1382572020. The cubic root of 55290 is about 38.0962472451.

The spelling of 55290 in words is "fifty-five thousand, two hundred ninety".