13321717621 has 4 divisors (see below), whose sum is σ = 13345130700. Its totient is φ = 13298304544.

The previous prime is 13321717583. The next prime is 13321717679. The reversal of 13321717621 is 12671712331.

13321717621 is nontrivially palindromic in base 14.

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 5228736100 + 8092981521 = 72310^2 + 89961^2 .

It is a cyclic number.

It is not a de Polignac number, because 13321717621 - 2¹¹ = 13321715573 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 (13321717121) 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, 11705686 + ... + 11706823.

It is an arithmetic number, because the mean of its divisors is an integer number (3336282675).

Almost surely, 2^13321717621 is an apocalyptic number.

It is an amenable number.

13321717621 is a deficient number, since it is larger than the sum of its proper divisors (23413079).

13321717621 is an equidigital number, since it uses as much as digits as its factorization.

13321717621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23413078.

The product of its digits is 10584, while the sum is 34.

The spelling of 13321717621 in words is "thirteen billion, three hundred twenty-one million, seven hundred seventeen thousand, six hundred twenty-one".