21013333321 has 8 divisors (see below), whose sum is σ = 21039124680. Its totient is φ = 20987561088.

The previous prime is 21013333307. The next prime is 21013333331. The reversal of 21013333321 is 12333331012.

It can be written as a sum of positive squares in 4 ways, for example, as 2097182025 + 18916151296 = 45795^2 + 137536^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21013333321 - 2⁷ = 21013333193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21013333292 and 21013333301.

It is not an unprimeable number, because it can be changed into a prime (21013333331) 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, 3703875 + ... + 3709543.

It is an arithmetic number, because the mean of its divisors is an integer number (2629890585).

Almost surely, 2^21013333321 is an apocalyptic number.

It is an amenable number.

21013333321 is a deficient number, since it is larger than the sum of its proper divisors (25791359).

21013333321 is a wasteful number, since it uses less digits than its factorization.

21013333321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9563.

The product of its (nonzero) digits is 972, while the sum is 22.

Adding to 21013333321 its reverse (12333331012), we get a palindrome (33346664333).

The spelling of 21013333321 in words is "twenty-one billion, thirteen million, three hundred thirty-three thousand, three hundred twenty-one".