21221033012 has 24 divisors (see below), whose sum is σ = 38906945280. Its totient is φ = 10114980480.

The previous prime is 21221032999. The next prime is 21221033017. The reversal of 21221033012 is 21033012212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221033017) 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 7 ways as a sum of consecutive naturals, for example, 1268837 + ... + 1285452.

It is an arithmetic number, because the mean of its divisors is an integer number (1621122720).

Almost surely, 2^21221033012 is an apocalyptic number.

It is an amenable number.

21221033012 is a deficient number, since it is larger than the sum of its proper divisors (17685912268).

21221033012 is a wasteful number, since it uses less digits than its factorization.

21221033012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2554391 (or 2554389 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21221033012 its reverse (21033012212), we get a palindrome (42254045224).

It can be divided in two parts, 212 and 21033012, that multiplied together give a palindrome (4458998544).

The spelling of 21221033012 in words is "twenty-one billion, two hundred twenty-one million, thirty-three thousand, twelve".