13653444221 has 4 divisors (see below), whose sum is σ = 13662363744. Its totient is φ = 13644524700.

The previous prime is 13653444199. The next prime is 13653444227. The reversal of 13653444221 is 12244435631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13653444221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13653444227) 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, 4457465 + ... + 4460526.

It is an arithmetic number, because the mean of its divisors is an integer number (3415590936).

Almost surely, 2^13653444221 is an apocalyptic number.

It is an amenable number.

13653444221 is a deficient number, since it is larger than the sum of its proper divisors (8919523).

13653444221 is an equidigital number, since it uses as much as digits as its factorization.

13653444221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8919522.

The product of its digits is 69120, while the sum is 35.

Adding to 13653444221 its reverse (12244435631), we get a palindrome (25897879852).

The spelling of 13653444221 in words is "thirteen billion, six hundred fifty-three million, four hundred forty-four thousand, two hundred twenty-one".