11221011111221 has 2 divisors, whose sum is σ = 11221011111222. Its totient is φ = 11221011111220.

The previous prime is 11221011111217. The next prime is 11221011111229. The reversal of 11221011111221 is 12211111012211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6485991591121 + 4735019520100 = 2546761^2 + 2176010^2 .

It is a cyclic number.

It is not a de Polignac number, because 11221011111221 - 2² = 11221011111217 is a prime.

It is a super-2 number, since 2×11221011111221² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 11221011111221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11221011111229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5610505555610 + 5610505555611.

It is an arithmetic number, because the mean of its divisors is an integer number (5610505555611).

Almost surely, 2^{11221011111221} is an apocalyptic number.

It is an amenable number.

11221011111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11221011111221 is an equidigital number, since it uses as much as digits as its factorization.

11221011111221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 11221011111221 its reverse (12211111012211), we get a palindrome (23432122123432).

It can be divided in two parts, 1122101 and 1111221, that added together give a palindrome (2233322).

The spelling of 11221011111221 in words is "eleven trillion, two hundred twenty-one billion, eleven million, one hundred eleven thousand, two hundred twenty-one".