55221030 has 96 divisors (see below), whose sum is σ = 154851840. Its totient is φ = 13608000.

The previous prime is 55221007. The next prime is 55221037. The reversal of 55221030 is 3012255.

It is a happy number.

55221030 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 55220994 and 55221012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55221037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 73155 + ... + 73905.

It is an arithmetic number, because the mean of its divisors is an integer number (1613040).

Almost surely, 2^55221030 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55221030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77425920).

55221030 is an abundant number, since it is smaller than the sum of its proper divisors (99630810).

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

55221030 is a wasteful number, since it uses less digits than its factorization.

55221030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826 (or 823 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 55221030 is about 7431.0853850565. The cubic root of 55221030 is about 380.8039994622.

Adding to 55221030 its reverse (3012255), we get a palindrome (58233285).

The spelling of 55221030 in words is "fifty-five million, two hundred twenty-one thousand, thirty".