55022221 has 2 divisors, whose sum is σ = 55022222. Its totient is φ = 55022220.

The previous prime is 55022213. The next prime is 55022237. The reversal of 55022221 is 12222055.

55022221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54552996 + 469225 = 7386^2 + 685^2 .

It is a cyclic number.

It is not a de Polignac number, because 55022221 - 2³ = 55022213 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55022521) 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 as a sum of consecutive naturals, namely, 27511110 + 27511111.

It is an arithmetic number, because the mean of its divisors is an integer number (27511111).

Almost surely, 2^55022221 is an apocalyptic number.

It is an amenable number.

55022221 is a deficient number, since it is larger than the sum of its proper divisors (1).

55022221 is an equidigital number, since it uses as much as digits as its factorization.

55022221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 55022221 is about 7417.6964753217. The cubic root of 55022221 is about 380.3464545783.

Adding to 55022221 its reverse (12222055), we get a palindrome (67244276).

The spelling of 55022221 in words is "fifty-five million, twenty-two thousand, two hundred twenty-one".