21211102120212 has 144 divisors (see below), whose sum is σ = 56851047052800. Its totient is φ = 6656349623040.

The previous prime is 21211102120211. The next prime is 21211102120231. The reversal of 21211102120212 is 21202120111212.

21211102120212 is a `hidden beast` number, since 21 + 211 + 10 + 212 + 0 + 212 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211102120211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 298464339 + ... + 298535397.

Almost surely, 2^{21211102120212} 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 21211102120212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28425523526400).

21211102120212 is an abundant number, since it is smaller than the sum of its proper divisors (35639944932588).

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

21211102120212 is a wasteful number, since it uses less digits than its factorization.

21211102120212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78366 (or 78361 counting only the distinct ones).

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

Adding to 21211102120212 its reverse (21202120111212), we get a palindrome (42413222231424).

The spelling of 21211102120212 in words is "twenty-one trillion, two hundred eleven billion, one hundred two million, one hundred twenty thousand, two hundred twelve".