2222211111221 has 2 divisors, whose sum is σ = 2222211111222. Its totient is φ = 2222211111220.

The previous prime is 2222211111217. The next prime is 2222211111251. The reversal of 2222211111221 is 1221111122222.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1296740175025 + 925470936196 = 1138745^2 + 962014^2 .

It is a cyclic number.

It is not a de Polignac number, because 2222211111221 - 2² = 2222211111217 is a prime.

It is a super-2 number, since 2×2222211111221² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2222211111193 and 2222211111202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2222211111251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1111105555610 + 1111105555611.

It is an arithmetic number, because the mean of its divisors is an integer number (1111105555611).

Almost surely, 2^{2222211111221} is an apocalyptic number.

It is an amenable number.

2222211111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2222211111221 is an equidigital number, since it uses as much as digits as its factorization.

2222211111221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 128, while the sum is 20.

Adding to 2222211111221 its reverse (1221111122222), we get a palindrome (3443322233443).

The spelling of 2222211111221 in words is "two trillion, two hundred twenty-two billion, two hundred eleven million, one hundred eleven thousand, two hundred twenty-one".