21221535303324 has 240 divisors, whose sum is σ = 57031070785920. Its totient is φ = 6879159705600.

The previous prime is 21221535303239. The next prime is 21221535303329. The reversal of 21221535303324 is 42330353512212.

21221535303324 is a `hidden beast` number, since 2 + 1 + 2 + 21 + 5 + 3 + 5 + 303 + 324 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221535303329) by changing a digit.

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 79 ways as a sum of consecutive naturals, for example, 498921562 + ... + 498964094.

It is an arithmetic number, because the mean of its divisors is an integer number (237629461608).

Almost surely, 2^{21221535303324} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21221535303324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28515535392960).

21221535303324 is an abundant number, since it is smaller than the sum of its proper divisors (35809535482596).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221535303324 is a wasteful number, since it uses less digits than its factorization.

21221535303324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42922 (or 42911 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 36.

Adding to 21221535303324 its reverse (42330353512212), we get a palindrome (63551888815536).

The spelling of 21221535303324 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred thirty-five million, three hundred three thousand, three hundred twenty-four".