20211112121111 has 4 divisors (see below), whose sum is σ = 20212109285400. Its totient is φ = 20210114956824.

The previous prime is 20211112121059. The next prime is 20211112121119. The reversal of 20211112121111 is 11112121111202.

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-20211112121111 is a prime.

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 20211112121111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211112121119) 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, 498551741 + ... + 498592278.

It is an arithmetic number, because the mean of its divisors is an integer number (5053027321350).

Almost surely, 2^{20211112121111} is an apocalyptic number.

20211112121111 is a deficient number, since it is larger than the sum of its proper divisors (997164289).

20211112121111 is an equidigital number, since it uses as much as digits as its factorization.

20211112121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997164288.

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

Adding to 20211112121111 its reverse (11112121111202), we get a palindrome (31323233232313).

It can be divided in two parts, 202 and 11112121111, that multiplied together give a palindrome (2244648464422).

The spelling of 20211112121111 in words is "twenty trillion, two hundred eleven billion, one hundred twelve million, one hundred twenty-one thousand, one hundred eleven".