21031331113221 has 64 divisors (see below), whose sum is σ = 34417618986240. Its totient is φ = 11247586560000.

The previous prime is 21031331113217. The next prime is 21031331113249. The reversal of 21031331113221 is 12231113313012.

It is not a de Polignac number, because 21031331113221 - 2² = 21031331113217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21031331113191 and 21031331113200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031331112221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7112200 + ... + 9625281.

It is an arithmetic number, because the mean of its divisors is an integer number (537775296660).

Almost surely, 2^{21031331113221} is an apocalyptic number.

It is an amenable number.

21031331113221 is a deficient number, since it is larger than the sum of its proper divisors (13386287873019).

21031331113221 is a wasteful number, since it uses less digits than its factorization.

21031331113221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16737638.

The product of its (nonzero) digits is 648, while the sum is 24.

Adding to 21031331113221 its reverse (12231113313012), we get a palindrome (33262444426233).

The spelling of 21031331113221 in words is "twenty-one trillion, thirty-one billion, three hundred thirty-one million, one hundred thirteen thousand, two hundred twenty-one".