21231203211 has 48 divisors (see below), whose sum is σ = 31750059744. Its totient is φ = 13661125632.

The previous prime is 21231203183. The next prime is 21231203243. The reversal of 21231203211 is 11230213212.

21231203211 is a `hidden beast` number, since 21 + 231 + 203 + 211 = 666.

It is not a de Polignac number, because 21231203211 - 2¹¹ = 21231201163 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21231203251) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 31084876 + ... + 31085558.

It is an arithmetic number, because the mean of its divisors is an integer number (661459578).

Almost surely, 2^21231203211 is an apocalyptic number.

21231203211 is a deficient number, since it is larger than the sum of its proper divisors (10518856533).

21231203211 is a wasteful number, since it uses less digits than its factorization.

21231203211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340 (or 1337 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21231203211 its reverse (11230213212), we get a palindrome (32461416423).

The spelling of 21231203211 in words is "twenty-one billion, two hundred thirty-one million, two hundred three thousand, two hundred eleven".