21220013212 has 12 divisors (see below), whose sum is σ = 37138551856. Its totient is φ = 10608998400.

The previous prime is 21220013203. The next prime is 21220013251. The reversal of 21220013212 is 21231002212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 203664 + ... + 289687.

Almost surely, 2^21220013212 is an apocalyptic number.

It is an amenable number.

21220013212 is a deficient number, since it is larger than the sum of its proper divisors (15918538644).

21220013212 is a wasteful number, since it uses less digits than its factorization.

21220013212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504108 (or 504106 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21220013212 its reverse (21231002212), we get a palindrome (42451015424).

The spelling of 21220013212 in words is "twenty-one billion, two hundred twenty million, thirteen thousand, two hundred twelve".