21212111202012 has 36 divisors (see below), whose sum is σ = 54140081027760. Its totient is φ = 7002056123712.

The previous prime is 21212111201999. The next prime is 21212111202059. The reversal of 21212111202012 is 21020211121212.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2860313337 + ... + 2860320752.

It is an arithmetic number, because the mean of its divisors is an integer number (1503891139660).

Almost surely, 2^{21212111202012} is an apocalyptic number.

It is an amenable number.

21212111202012 is an abundant number, since it is smaller than the sum of its proper divisors (32927969825748).

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

21212111202012 is a wasteful number, since it uses less digits than its factorization.

21212111202012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5720634202 (or 5720634197 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21212111202012 its reverse (21020211121212), we get a palindrome (42232322323224).

The spelling of 21212111202012 in words is "twenty-one trillion, two hundred twelve billion, one hundred eleven million, two hundred two thousand, twelve".