21211211211212 has 24 divisors (see below), whose sum is σ = 41355707742720. Its totient is φ = 9436322201360.

The previous prime is 21211211211199. The next prime is 21211211211217.

It is a happy number.

21211211211212 is nontrivially palindromic in base 10.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21211211211217) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 5128433912 + ... + 5128438047.

It is an arithmetic number, because the mean of its divisors is an integer number (1723154489280).

Almost surely, 2^{21211211211212} is an apocalyptic number.

21211211211212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21211211211212 is a deficient number, since it is larger than the sum of its proper divisors (20144496531508).

21211211211212 is a wasteful number, since it uses less digits than its factorization.

21211211211212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10256872021 (or 10256872019 counting only the distinct ones).

The product of its digits is 64, while the sum is 20.

It can be divided in two parts, 2121121 and 1211212, that added together give a palindrome (3332333).

The spelling of 21211211211212 in words is "twenty-one trillion, two hundred eleven billion, two hundred eleven million, two hundred eleven thousand, two hundred twelve".