21131331112 has 32 divisors (see below), whose sum is σ = 39844385280. Its totient is φ = 10506323520.

The previous prime is 21131331077. The next prime is 21131331113. The reversal of 21131331112 is 21113313112.

It is a self number, because there is not a number n which added to its sum of digits gives 21131331112.

It is not an unprimeable number, because it can be changed into a prime (21131331113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1075537 + ... + 1095007.

It is an arithmetic number, because the mean of its divisors is an integer number (1245137040).

Almost surely, 2^21131331112 is an apocalyptic number.

It is an amenable number.

21131331112 is a deficient number, since it is larger than the sum of its proper divisors (18713054168).

21131331112 is a wasteful number, since it uses less digits than its factorization.

21131331112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20233 (or 20229 counting only the distinct ones).

The product of its digits is 108, while the sum is 19.

Adding to 21131331112 its reverse (21113313112), we get a palindrome (42244644224).

The spelling of 21131331112 in words is "twenty-one billion, one hundred thirty-one million, three hundred thirty-one thousand, one hundred twelve".