21331012231 has 16 divisors (see below), whose sum is σ = 22188434688. Its totient is φ = 20490624000.

The previous prime is 21331012217. The next prime is 21331012243. The reversal of 21331012231 is 13221013312.

It is a cyclic number.

It is not a de Polignac number, because 21331012231 - 2⁹ = 21331011719 is a prime.

It is a super-2 number, since 2×21331012231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21331012199 and 21331012208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331012211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1840906 + ... + 1852456.

It is an arithmetic number, because the mean of its divisors is an integer number (1386777168).

Almost surely, 2^21331012231 is an apocalyptic number.

21331012231 is a deficient number, since it is larger than the sum of its proper divisors (857422457).

21331012231 is a wasteful number, since it uses less digits than its factorization.

21331012231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12282.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21331012231 its reverse (13221013312), we get a palindrome (34552025543).

The spelling of 21331012231 in words is "twenty-one billion, three hundred thirty-one million, twelve thousand, two hundred thirty-one".