20112112211111 has 4 divisors (see below), whose sum is σ = 21295177635312. Its totient is φ = 18929046786912.

The previous prime is 20112112211101. The next prime is 20112112211117. The reversal of 20112112211111 is 11111221121102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20112112211111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1183065424183 = 20112112211111 / (2 + 0 + 1 + 1 + 2 + 1 + 1 + 2 + 2 + 1 + 1 + 1 + 1 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20112112211111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112112211117) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 591532712075 + ... + 591532712108.

It is an arithmetic number, because the mean of its divisors is an integer number (5323794408828).

Almost surely, 2^{20112112211111} is an apocalyptic number.

20112112211111 is a deficient number, since it is larger than the sum of its proper divisors (1183065424201).

20112112211111 is a wasteful number, since it uses less digits than its factorization.

20112112211111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1183065424200.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 20112112211111 its reverse (11111221121102), we get a palindrome (31223333332213).

The spelling of 20112112211111 in words is "twenty trillion, one hundred twelve billion, one hundred twelve million, two hundred eleven thousand, one hundred eleven".