21221332312 has 32 divisors (see below), whose sum is σ = 39880018080. Its totient is φ = 10586695680.

The previous prime is 21221332289. The next prime is 21221332343. The reversal of 21221332312 is 21323312212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10042168 + ... + 10044280.

It is an arithmetic number, because the mean of its divisors is an integer number (1246250565).

Almost surely, 2^21221332312 is an apocalyptic number.

It is an amenable number.

21221332312 is a deficient number, since it is larger than the sum of its proper divisors (18658685768).

21221332312 is a wasteful number, since it uses less digits than its factorization.

21221332312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4363 (or 4359 counting only the distinct ones).

The product of its digits is 864, while the sum is 22.

Adding to 21221332312 its reverse (21323312212), we get a palindrome (42544644524).

The spelling of 21221332312 in words is "twenty-one billion, two hundred twenty-one million, three hundred thirty-two thousand, three hundred twelve".