55222220 has 12 divisors (see below), whose sum is σ = 115966704. Its totient is φ = 22088880.

The previous prime is 55222207. The next prime is 55222229. The reversal of 55222220 is 2222255.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2761111 = 55222220 / (5 + 5 + 2 + 2 + 2 + 2 + 2 + 0).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 55222192 and 55222201.

It is not an unprimeable number, because it can be changed into a prime (55222229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1380536 + ... + 1380575.

It is an arithmetic number, because the mean of its divisors is an integer number (9663892).

Almost surely, 2^55222220 is an apocalyptic number.

It is an amenable number.

55222220 is an abundant number, since it is smaller than the sum of its proper divisors (60744484).

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

55222220 is a wasteful number, since it uses less digits than its factorization.

55222220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2761120 (or 2761118 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 55222220 is about 7431.1654536822. The cubic root of 55222220 is about 380.8067348543.

Adding to 55222220 its reverse (2222255), we get a palindrome (57444475).

It can be divided in two parts, 5 and 5222220, that added together give a palindrome (5222225).

The spelling of 55222220 in words is "fifty-five million, two hundred twenty-two thousand, two hundred twenty".