21210211111212 has 18 divisors (see below), whose sum is σ = 53614700308988. Its totient is φ = 7070070370392.

The previous prime is 21210211111181. The next prime is 21210211111217. The reversal of 21210211111212 is 21211111201212.

It is a happy number.

21210211111212 is a `hidden beast` number, since 21 + 210 + 211 + 1 + 11 + 212 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

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

It is not an unprimeable number, because it can be changed into a prime (21210211111217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 294586265398 + ... + 294586265469.

Almost surely, 2^{21210211111212} is an apocalyptic number.

It is an amenable number.

21210211111212 is an abundant number, since it is smaller than the sum of its proper divisors (32404489197776).

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

21210211111212 is a wasteful number, since it uses less digits than its factorization.

21210211111212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589172530877 (or 589172530872 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21210211111212 its reverse (21211111201212), we get a palindrome (42421322312424).

The spelling of 21210211111212 in words is "twenty-one trillion, two hundred ten billion, two hundred eleven million, one hundred eleven thousand, two hundred twelve".