221000222221 has 2 divisors, whose sum is σ = 221000222222. Its totient is φ = 221000222220.

The previous prime is 221000222203. The next prime is 221000222231. The reversal of 221000222221 is 122222000122.

221000222221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 192646377225 + 28353844996 = 438915^2 + 168386^2 .

It is a cyclic number.

It is not a de Polignac number, because 221000222221 - 2¹⁷ = 221000091149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221000222195 and 221000222204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221000222231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110500111110 + 110500111111.

It is an arithmetic number, because the mean of its divisors is an integer number (110500111111).

Almost surely, 2^221000222221 is an apocalyptic number.

It is an amenable number.

221000222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

221000222221 is an equidigital number, since it uses as much as digits as its factorization.

221000222221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 221000222221 its reverse (122222000122), we get a palindrome (343222222343).

The spelling of 221000222221 in words is "two hundred twenty-one billion, two hundred twenty-two thousand, two hundred twenty-one".