2123122121111 has 4 divisors (see below), whose sum is σ = 2123784978552. Its totient is φ = 2122459263672.

The previous prime is 2123122120997. The next prime is 2123122121177. The reversal of 2123122121111 is 1111212213212.

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-2123122121111 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 (2123122121611) 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, 331423916 + ... + 331430321.

It is an arithmetic number, because the mean of its divisors is an integer number (530946244638).

Almost surely, 2^{2123122121111} is an apocalyptic number.

2123122121111 is a deficient number, since it is larger than the sum of its proper divisors (662857441).

2123122121111 is an equidigital number, since it uses as much as digits as its factorization.

2123122121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662857440.

The product of its digits is 96, while the sum is 20.

Adding to 2123122121111 its reverse (1111212213212), we get a palindrome (3234334334323).

The spelling of 2123122121111 in words is "two trillion, one hundred twenty-three billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred eleven".