21023013331221 has 32 divisors (see below), whose sum is σ = 32413387327488. Its totient is φ = 11978515050240.

The previous prime is 21023013331193. The next prime is 21023013331237. The reversal of 21023013331221 is 12213331032012.

It is not a de Polignac number, because 21023013331221 - 2¹⁸ = 21023013069077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21023013331191 and 21023013331200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023013332221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20149485 + ... + 21167138.

It is an arithmetic number, because the mean of its divisors is an integer number (1012918353984).

Almost surely, 2^{21023013331221} is an apocalyptic number.

It is an amenable number.

21023013331221 is a deficient number, since it is larger than the sum of its proper divisors (11390373996267).

21023013331221 is a wasteful number, since it uses less digits than its factorization.

21023013331221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41317561.

The product of its (nonzero) digits is 1296, while the sum is 24.

Adding to 21023013331221 its reverse (12213331032012), we get a palindrome (33236344363233).

The spelling of 21023013331221 in words is "twenty-one trillion, twenty-three billion, thirteen million, three hundred thirty-one thousand, two hundred twenty-one".