21212010211212 has 288 divisors, whose sum is σ = 57260396793600. Its totient is φ = 6612145053696.

The previous prime is 21212010211207. The next prime is 21212010211247. The reversal of 21212010211212 is 21211201021212.

21212010211212 is a `hidden beast` number, since 21 + 21 + 201 + 0 + 211 + 212 = 666.

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

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 95 ways as a sum of consecutive naturals, for example, 771079714 + ... + 771107222.

It is an arithmetic number, because the mean of its divisors is an integer number (198820822200).

Almost surely, 2^{21212010211212} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21212010211212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28630198396800).

21212010211212 is an abundant number, since it is smaller than the sum of its proper divisors (36048386582388).

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

21212010211212 is a wasteful number, since it uses less digits than its factorization.

21212010211212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27825 (or 27820 counting only the distinct ones).

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

Adding to 21212010211212 its reverse (21211201021212), we get a palindrome (42423211232424).

The spelling of 21212010211212 in words is "twenty-one trillion, two hundred twelve billion, ten million, two hundred eleven thousand, two hundred twelve".