55440220 has 24 divisors (see below), whose sum is σ = 127009008. Its totient is φ = 20160000.

The previous prime is 55440211. The next prime is 55440223. The reversal of 55440220 is 2204455.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 55440191 and 55440200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55440223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 125781 + ... + 126220.

It is an arithmetic number, because the mean of its divisors is an integer number (5292042).

Almost surely, 2^55440220 is an apocalyptic number.

It is an amenable number.

55440220 is an abundant number, since it is smaller than the sum of its proper divisors (71568788).

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

55440220 is a wasteful number, since it uses less digits than its factorization.

55440220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252021 (or 252019 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 22.

The square root of 55440220 is about 7445.8189610009. The cubic root of 55440220 is about 381.3071787393.

Adding to 55440220 its reverse (2204455), we get a palindrome (57644675).

The spelling of 55440220 in words is "fifty-five million, four hundred forty thousand, two hundred twenty".