13502531442221 has 4 divisors (see below), whose sum is σ = 13636219872444. Its totient is φ = 13368843012000.

The previous prime is 13502531442209. The next prime is 13502531442329. The reversal of 13502531442221 is 12224413520531.

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 12682394725225 + 820136716996 = 3561235^2 + 905614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13502531442221 is a prime.

It is a super-2 number, since 2×13502531442221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13502531442721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66844214960 + ... + 66844215161.

It is an arithmetic number, because the mean of its divisors is an integer number (3409054968111).

Almost surely, 2^{13502531442221} is an apocalyptic number.

It is an amenable number.

13502531442221 is a deficient number, since it is larger than the sum of its proper divisors (133688430223).

13502531442221 is a wasteful number, since it uses less digits than its factorization.

13502531442221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133688430222.

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 13502531442221 its reverse (12224413520531), we get a palindrome (25726944962752).

The spelling of 13502531442221 in words is "thirteen trillion, five hundred two billion, five hundred thirty-one million, four hundred forty-two thousand, two hundred twenty-one".