21043212111 has 12 divisors (see below), whose sum is σ = 30426435520. Its totient is φ = 14014645920.

The previous prime is 21043212109. The next prime is 21043212137. The reversal of 21043212111 is 11121234012.

21043212111 is a `hidden beast` number, since 21 + 0 + 432 + 1 + 211 + 1 = 666.

It is not a de Polignac number, because 21043212111 - 2¹ = 21043212109 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 (21043212181) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1170766 + ... + 1188603.

Almost surely, 2^21043212111 is an apocalyptic number.

21043212111 is a deficient number, since it is larger than the sum of its proper divisors (9383223409).

21043212111 is a wasteful number, since it uses less digits than its factorization.

21043212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360366 (or 2360363 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21043212111 its reverse (11121234012), we get a palindrome (32164446123).

The spelling of 21043212111 in words is "twenty-one billion, forty-three million, two hundred twelve thousand, one hundred eleven".