21112023211 has 4 divisors (see below), whose sum is σ = 21125566800. Its totient is φ = 21098479624.

The previous prime is 21112023193. The next prime is 21112023221. The reversal of 21112023211 is 11232021112.

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-21112023211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21112023221) 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, 6769456 + ... + 6772573.

It is an arithmetic number, because the mean of its divisors is an integer number (5281391700).

Almost surely, 2^21112023211 is an apocalyptic number.

21112023211 is a deficient number, since it is larger than the sum of its proper divisors (13543589).

21112023211 is a wasteful number, since it uses less digits than its factorization.

21112023211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13543588.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21112023211 its reverse (11232021112), we get a palindrome (32344044323).

The spelling of 21112023211 in words is "twenty-one billion, one hundred twelve million, twenty-three thousand, two hundred eleven".