1011221112221 has 2 divisors, whose sum is σ = 1011221112222. Its totient is φ = 1011221112220.

The previous prime is 1011221112169. The next prime is 1011221112259. The reversal of 1011221112221 is 1222111221101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 667180209721 + 344040902500 = 816811^2 + 586550^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011221112221 - 2⁶ = 1011221112157 is a prime.

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 1011221112221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011221111221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505610556110 + 505610556111.

It is an arithmetic number, because the mean of its divisors is an integer number (505610556111).

Almost surely, 2^{1011221112221} is an apocalyptic number.

It is an amenable number.

1011221112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011221112221 is an equidigital number, since it uses as much as digits as its factorization.

1011221112221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1011221112221 its reverse (1222111221101), we get a palindrome (2233332333322).

The spelling of 1011221112221 in words is "one trillion, eleven billion, two hundred twenty-one million, one hundred twelve thousand, two hundred twenty-one".