2123021111 has 4 divisors (see below), whose sum is σ = 2144041224. Its totient is φ = 2102001000.

The previous prime is 2123021099. The next prime is 2123021119. The reversal of 2123021111 is 1111203212.

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-2123021111 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 (2123021119) 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, 10509905 + ... + 10510106.

It is an arithmetic number, because the mean of its divisors is an integer number (536010306).

Almost surely, 2^2123021111 is an apocalyptic number.

2123021111 is a deficient number, since it is larger than the sum of its proper divisors (21020113).

2123021111 is a wasteful number, since it uses less digits than its factorization.

2123021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21020112.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 2123021111 is about 46076.2532222402. The cubic root of 2123021111 is about 1285.2415905333.

Adding to 2123021111 its reverse (1111203212), we get a palindrome (3234224323).

The spelling of 2123021111 in words is "two billion, one hundred twenty-three million, twenty-one thousand, one hundred eleven".