21212001212212 has 24 divisors (see below), whose sum is σ = 37244070855936. Its totient is φ = 10570846248768.

The previous prime is 21212001212209. The next prime is 21212001212219. The reversal of 21212001212212 is 21221210021212.

It is a self number, because there is not a number n which added to its sum of digits gives 21212001212212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212001212219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9457533 + ... + 11483419.

It is an arithmetic number, because the mean of its divisors is an integer number (1551836285664).

Almost surely, 2^{21212001212212} is an apocalyptic number.

It is an amenable number.

21212001212212 is a deficient number, since it is larger than the sum of its proper divisors (16032069643724).

21212001212212 is a wasteful number, since it uses less digits than its factorization.

21212001212212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2034567 (or 2034565 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21212001212212 its reverse (21221210021212), we get a palindrome (42433211233424).

The spelling of 21212001212212 in words is "twenty-one trillion, two hundred twelve billion, one million, two hundred twelve thousand, two hundred twelve".