13531230221 has 4 divisors (see below), whose sum is σ = 13547712444. Its totient is φ = 13514748000.

The previous prime is 13531230217. The next prime is 13531230253. The reversal of 13531230221 is 12203213531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12203213531 = 233 ⋅52374307.

It can be written as a sum of positive squares in 2 ways, for example, as 1073545225 + 12457684996 = 32765^2 + 111614^2 .

It is a cyclic number.

It is not a de Polignac number, because 13531230221 - 2² = 13531230217 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 (13531230281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8239880 + ... + 8241521.

It is an arithmetic number, because the mean of its divisors is an integer number (3386928111).

Almost surely, 2^13531230221 is an apocalyptic number.

It is an amenable number.

13531230221 is a deficient number, since it is larger than the sum of its proper divisors (16482223).

13531230221 is an equidigital number, since it uses as much as digits as its factorization.

13531230221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16482222.

The product of its (nonzero) digits is 1080, while the sum is 23.

Adding to 13531230221 its reverse (12203213531), we get a palindrome (25734443752).

The spelling of 13531230221 in words is "thirteen billion, five hundred thirty-one million, two hundred thirty thousand, two hundred twenty-one".