21111021201212 has 12 divisors (see below), whose sum is σ = 36948243929520. Its totient is φ = 10554380078496.

The previous prime is 21111021201181. The next prime is 21111021201271. The reversal of 21111021201212 is 21210212011112.

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, 282588512 + ... + 282663207.

It is an arithmetic number, because the mean of its divisors is an integer number (3079020327460).

Almost surely, 2^{21111021201212} is an apocalyptic number.

It is an amenable number.

21111021201212 is a deficient number, since it is larger than the sum of its proper divisors (15837222728308).

21111021201212 is a wasteful number, since it uses less digits than its factorization.

21111021201212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565261060 (or 565261058 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21111021201212 its reverse (21210212011112), we get a palindrome (42321233212324).

The spelling of 21111021201212 in words is "twenty-one trillion, one hundred eleven billion, twenty-one million, two hundred one thousand, two hundred twelve".