20111111210111 has 16 divisors (see below), whose sum is σ = 20270407908000. Its totient is φ = 19952147432448.

The previous prime is 20111111210093. The next prime is 20111111210149. The reversal of 20111111210111 is 11101211111102.

It is a cyclic number.

It is not a de Polignac number, because 20111111210111 - 2³⁸ = 19836233303167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111111213111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 913009880 + ... + 913031906.

It is an arithmetic number, because the mean of its divisors is an integer number (1266900494250).

Almost surely, 2^{20111111210111} is an apocalyptic number.

20111111210111 is a deficient number, since it is larger than the sum of its proper divisors (159296697889).

20111111210111 is a wasteful number, since it uses less digits than its factorization.

20111111210111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29258.

The product of its (nonzero) digits is 4, while the sum is 14.

Adding to 20111111210111 its reverse (11101211111102), we get a palindrome (31212322321213).

Subtracting from 20111111210111 its reverse (11101211111102), we obtain a palindrome (9009900099009).

The spelling of 20111111210111 in words is "twenty trillion, one hundred eleven billion, one hundred eleven million, two hundred ten thousand, one hundred eleven".