21263111212 has 24 divisors (see below), whose sum is σ = 42544246304. Its totient is φ = 9108899712.

The previous prime is 21263111209. The next prime is 21263111297. The reversal of 21263111212 is 21211136212.

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, 93183 + ... + 226294.

Almost surely, 2^21263111212 is an apocalyptic number.

It is an amenable number.

21263111212 is an abundant number, since it is smaller than the sum of its proper divisors (21281135092).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21263111212 is a wasteful number, since it uses less digits than its factorization.

21263111212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321865 (or 321863 counting only the distinct ones).

The product of its digits is 288, while the sum is 22.

Adding to 21263111212 its reverse (21211136212), we get a palindrome (42474247424).

The spelling of 21263111212 in words is "twenty-one billion, two hundred sixty-three million, one hundred eleven thousand, two hundred twelve".