20111222191 has 2 divisors, whose sum is σ = 20111222192. Its totient is φ = 20111222190.

The previous prime is 20111222189. The next prime is 20111222203. The reversal of 20111222191 is 19122211102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20111222191 - 2¹ = 20111222189 is a prime.

It is a super-2 number, since 2×20111222191² (a number of 21 digits) contains 22 as substring.

Together with 20111222189, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20111222161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055611095 + 10055611096.

It is an arithmetic number, because the mean of its divisors is an integer number (10055611096).

Almost surely, 2^20111222191 is an apocalyptic number.

20111222191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111222191 is an equidigital number, since it uses as much as digits as its factorization.

20111222191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 20111222191 its reverse (19122211102), we get a palindrome (39233433293).

The spelling of 20111222191 in words is "twenty billion, one hundred eleven million, two hundred twenty-two thousand, one hundred ninety-one".