21343313221 has 4 divisors (see below), whose sum is σ = 22598802252. Its totient is φ = 20087824192.

The previous prime is 21343313213. The next prime is 21343313231. The reversal of 21343313221 is 12231334312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16962197121 + 4381116100 = 130239^2 + 66190^2 .

It is a cyclic number.

It is not a de Polignac number, because 21343313221 - 2³ = 21343313213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21343313231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 627744490 + ... + 627744523.

It is an arithmetic number, because the mean of its divisors is an integer number (5649700563).

Almost surely, 2^21343313221 is an apocalyptic number.

It is an amenable number.

21343313221 is a deficient number, since it is larger than the sum of its proper divisors (1255489031).

21343313221 is a wasteful number, since it uses less digits than its factorization.

21343313221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1255489030.

The product of its digits is 2592, while the sum is 25.

Adding to 21343313221 its reverse (12231334312), we get a palindrome (33574647533).

The spelling of 21343313221 in words is "twenty-one billion, three hundred forty-three million, three hundred thirteen thousand, two hundred twenty-one".