21013311313221 has 16 divisors (see below), whose sum is σ = 28669468185600. Its totient is φ = 13683017602800.

The previous prime is 21013311313219. The next prime is 21013311313229. The reversal of 21013311313221 is 12231311331012.

It is not a de Polignac number, because 21013311313221 - 2¹ = 21013311313219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21013311313191 and 21013311313200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013311313229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43510330 + ... + 43990628.

It is an arithmetic number, because the mean of its divisors is an integer number (1791841761600).

Almost surely, 2^{21013311313221} is an apocalyptic number.

It is an amenable number.

21013311313221 is a deficient number, since it is larger than the sum of its proper divisors (7656156872379).

21013311313221 is a wasteful number, since it uses less digits than its factorization.

21013311313221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819496.

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

Adding to 21013311313221 its reverse (12231311331012), we get a palindrome (33244622644233).

The spelling of 21013311313221 in words is "twenty-one trillion, thirteen billion, three hundred eleven million, three hundred thirteen thousand, two hundred twenty-one".