21133113212 has 12 divisors (see below), whose sum is σ = 36985362120. Its totient is φ = 10565866896.

The previous prime is 21133113203. The next prime is 21133113233. The reversal of 21133113212 is 21231133112.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100118 + ... + 228669.

It is an arithmetic number, because the mean of its divisors is an integer number (3082113510).

Almost surely, 2^21133113212 is an apocalyptic number.

It is an amenable number.

21133113212 is a deficient number, since it is larger than the sum of its proper divisors (15852248908).

21133113212 is a wasteful number, since it uses less digits than its factorization.

21133113212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344860 (or 344858 counting only the distinct ones).

The product of its digits is 216, while the sum is 20.

Adding to 21133113212 its reverse (21231133112), we get a palindrome (42364246324).

The spelling of 21133113212 in words is "twenty-one billion, one hundred thirty-three million, one hundred thirteen thousand, two hundred twelve".