21214203124221 has 16 divisors (see below), whose sum is σ = 31429942315200. Its totient is φ = 14142130123824.

The previous prime is 21214203124151. The next prime is 21214203124223. The reversal of 21214203124221 is 12242130241212.

21214203124221 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 420 + 3 + 12 + 4 + 221 = 666.

It is not a de Polignac number, because 21214203124221 - 2³⁹ = 20664447310333 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21214203124223) 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, 18086406 + ... + 19223591.

It is an arithmetic number, because the mean of its divisors is an integer number (1964371394700).

Almost surely, 2^{21214203124221} is an apocalyptic number.

It is an amenable number.

21214203124221 is a deficient number, since it is larger than the sum of its proper divisors (10215739190979).

21214203124221 is a wasteful number, since it uses less digits than its factorization.

21214203124221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37331065 (or 37331059 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

Adding to 21214203124221 its reverse (12242130241212), we get a palindrome (33456333365433).

The spelling of 21214203124221 in words is "twenty-one trillion, two hundred fourteen billion, two hundred three million, one hundred twenty-four thousand, two hundred twenty-one".