21122001021212 has 96 divisors (see below), whose sum is σ = 46974425186304. Its totient is φ = 8084110521600.

The previous prime is 21122001021211. The next prime is 21122001021223. The reversal of 21122001021212 is 21212010022112.

It is a super-2 number, since 2×21122001021212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122001021211) 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 31 ways as a sum of consecutive naturals, for example, 39692333 + ... + 40220955.

It is an arithmetic number, because the mean of its divisors is an integer number (489316929024).

Almost surely, 2^{21122001021212} 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 21122001021212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23487212593152).

21122001021212 is an abundant number, since it is smaller than the sum of its proper divisors (25852424165092).

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

21122001021212 is a wasteful number, since it uses less digits than its factorization.

21122001021212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532219 (or 532217 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21122001021212 its reverse (21212010022112), we get a palindrome (42334011043324).

The spelling of 21122001021212 in words is "twenty-one trillion, one hundred twenty-two billion, one million, twenty-one thousand, two hundred twelve".