20111112221 has 2 divisors, whose sum is σ = 20111112222. Its totient is φ = 20111112220.

The previous prime is 20111112199. The next prime is 20111112233. The reversal of 20111112221 is 12221111102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20064722500 + 46389721 = 141650^2 + 6811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20111112221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20111112196 and 20111112205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20111112121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055556110 + 10055556111.

It is an arithmetic number, because the mean of its divisors is an integer number (10055556111).

Almost surely, 2^20111112221 is an apocalyptic number.

It is an amenable number.

20111112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111112221 is an equidigital number, since it uses as much as digits as its factorization.

20111112221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 20111112221 its reverse (12221111102), we get a palindrome (32332223323).

The spelling of 20111112221 in words is "twenty billion, one hundred eleven million, one hundred twelve thousand, two hundred twenty-one".