2011111122221 has 2 divisors, whose sum is σ = 2011111122222. Its totient is φ = 2011111122220.

The previous prime is 2011111122211. The next prime is 2011111122239. The reversal of 2011111122221 is 1222211111102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1164920869225 + 846190252996 = 1079315^2 + 919886^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011111122221 - 2²² = 2011106927917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2011111122221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011111122211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005555561110 + 1005555561111.

It is an arithmetic number, because the mean of its divisors is an integer number (1005555561111).

Almost surely, 2^{2011111122221} is an apocalyptic number.

It is an amenable number.

2011111122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011111122221 is an equidigital number, since it uses as much as digits as its factorization.

2011111122221 is an odious number, because the sum of its binary digits is odd.

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

Adding to 2011111122221 its reverse (1222211111102), we get a palindrome (3233322233323).

The spelling of 2011111122221 in words is "two trillion, eleven billion, one hundred eleven million, one hundred twenty-two thousand, two hundred twenty-one".