21212244422421 has 32 divisors (see below), whose sum is σ = 32558087261952. Its totient is φ = 12181597232640.

The previous prime is 21212244422401. The next prime is 21212244422431. The reversal of 21212244422421 is 12422444221212.

It is not a de Polignac number, because 21212244422421 - 2¹⁵ = 21212244389653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212244422401) 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, 288353310 + ... + 288426863.

It is an arithmetic number, because the mean of its divisors is an integer number (1017440226936).

Almost surely, 2^{21212244422421} is an apocalyptic number.

It is an amenable number.

21212244422421 is a deficient number, since it is larger than the sum of its proper divisors (11345842839531).

21212244422421 is a wasteful number, since it uses less digits than its factorization.

21212244422421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576780253.

The product of its digits is 32768, while the sum is 33.

Adding to 21212244422421 its reverse (12422444221212), we get a palindrome (33634688643633).

The spelling of 21212244422421 in words is "twenty-one trillion, two hundred twelve billion, two hundred forty-four million, four hundred twenty-two thousand, four hundred twenty-one".