21201322212 has 96 divisors (see below), whose sum is σ = 63703664640. Its totient is φ = 5972188320.

The previous prime is 21201322171. The next prime is 21201322213. The reversal of 21201322212 is 21222310212.

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 (21201322213) 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 31 ways as a sum of consecutive naturals, for example, 143818 + ... + 251169.

It is an arithmetic number, because the mean of its divisors is an integer number (663579840).

Almost surely, 2^21201322212 is an apocalyptic number.

It is an amenable number.

21201322212 is an abundant number, since it is smaller than the sum of its proper divisors (42502342428).

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

21201322212 is a wasteful number, since it uses less digits than its factorization.

21201322212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395078 (or 395070 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21201322212 its reverse (21222310212), we get a palindrome (42423632424).

The spelling of 21201322212 in words is "twenty-one billion, two hundred one million, three hundred twenty-two thousand, two hundred twelve".