21200111212 has 24 divisors (see below), whose sum is σ = 43302357504. Its totient is φ = 8892447312.

The previous prime is 21200111167. The next prime is 21200111279. The reversal of 21200111212 is 21211100212.

It is a junction number, because it is equal to n+sod(n) for n = 21200111192 and 21200111201.

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, 8053438 + ... + 8056069.

It is an arithmetic number, because the mean of its divisors is an integer number (1804264896).

Almost surely, 2^21200111212 is an apocalyptic number.

It is an amenable number.

21200111212 is an abundant number, since it is smaller than the sum of its proper divisors (22102246292).

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

21200111212 is a wasteful number, since it uses less digits than its factorization.

21200111212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16109565 (or 16109563 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21200111212 its reverse (21211100212), we get a palindrome (42411211424).

The spelling of 21200111212 in words is "twenty-one billion, two hundred million, one hundred eleven thousand, two hundred twelve".