21201212212212 has 96 divisors (see below), whose sum is σ = 50384062310400. Its totient is φ = 6936786974592.

The previous prime is 21201212212181. The next prime is 21201212212231. The reversal of 21201212212212 is 21221221210212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2398594089 + ... + 2398602927.

It is an arithmetic number, because the mean of its divisors is an integer number (524833982400).

Almost surely, 2^{21201212212212} is an apocalyptic number.

It is an amenable number.

21201212212212 is an abundant number, since it is smaller than the sum of its proper divisors (29182850098188).

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

21201212212212 is a wasteful number, since it uses less digits than its factorization.

21201212212212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13645 (or 13643 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21201212212212 its reverse (21221221210212), we get a palindrome (42422433422424).

The spelling of 21201212212212 in words is "twenty-one trillion, two hundred one billion, two hundred twelve million, two hundred twelve thousand, two hundred twelve".