21212310313221 has 8 divisors (see below), whose sum is σ = 28283106784800. Its totient is φ = 14141527025232.

The previous prime is 21212310313141. The next prime is 21212310313237. The reversal of 21212310313221 is 12231301321212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21212310313221 - 2¹⁹ = 21212309788933 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212310313191 and 21212310313200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212310313721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1424026 + ... + 6667268.

It is an arithmetic number, because the mean of its divisors is an integer number (3535388348100).

Almost surely, 2^{21212310313221} is an apocalyptic number.

It is an amenable number.

21212310313221 is a deficient number, since it is larger than the sum of its proper divisors (7070796471579).

21212310313221 is a wasteful number, since it uses less digits than its factorization.

21212310313221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6591795.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21212310313221 its reverse (12231301321212), we get a palindrome (33443611634433).

The spelling of 21212310313221 in words is "twenty-one trillion, two hundred twelve billion, three hundred ten million, three hundred thirteen thousand, two hundred twenty-one".