55112220 has 72 divisors (see below), whose sum is σ = 168045696. Its totient is φ = 14620032.

The previous prime is 55112207. The next prime is 55112221. The reversal of 55112220 is 2221155.

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

It is a junction number, because it is equal to n+sod(n) for n = 55112193 and 55112202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55112221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 39454 + ... + 40826.

It is an arithmetic number, because the mean of its divisors is an integer number (2333968).

Almost surely, 2^55112220 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 55112220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84022848).

55112220 is an abundant number, since it is smaller than the sum of its proper divisors (112933476).

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

55112220 is a wasteful number, since it uses less digits than its factorization.

55112220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1611 (or 1606 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 55112220 is about 7423.7605026024. The cubic root of 55112220 is about 380.5537172278.

Adding to 55112220 its reverse (2221155), we get a palindrome (57333375).

The spelling of 55112220 in words is "fifty-five million, one hundred twelve thousand, two hundred twenty".