21444022421421 has 16 divisors (see below), whose sum is σ = 30977958521664. Its totient is φ = 13142164218624.

The previous prime is 21444022421407. The next prime is 21444022421429. The reversal of 21444022421421 is 12412422044412.

It is a happy number.

It is not a de Polignac number, because 21444022421421 - 2⁶ = 21444022421357 is a prime.

It is a super-2 number, since 2×21444022421421² (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 (21444022421429) 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 15 ways as a sum of consecutive naturals, for example, 4889195806 + ... + 4889200191.

It is an arithmetic number, because the mean of its divisors is an integer number (1936122407604).

Almost surely, 2^{21444022421421} is an apocalyptic number.

It is an amenable number.

21444022421421 is a deficient number, since it is larger than the sum of its proper divisors (9533936100243).

21444022421421 is a wasteful number, since it uses less digits than its factorization.

21444022421421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9778396060.

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

Adding to 21444022421421 its reverse (12412422044412), we get a palindrome (33856444465833).

The spelling of 21444022421421 in words is "twenty-one trillion, four hundred forty-four billion, twenty-two million, four hundred twenty-one thousand, four hundred twenty-one".