13513221 has 12 divisors (see below), whose sum is σ = 19579872. Its totient is φ = 8980776.

The previous prime is 13513153. The next prime is 13513243. The reversal of 13513221 is 12231531.

It is a de Polignac number, because none of the positive numbers 2^k-13513221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13513194 and 13513203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13513021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 960 + ... + 5286.

It is an arithmetic number, because the mean of its divisors is an integer number (1631656).

Almost surely, 2^13513221 is an apocalyptic number.

It is an amenable number.

13513221 is a deficient number, since it is larger than the sum of its proper divisors (6066651).

13513221 is a wasteful number, since it uses less digits than its factorization.

13513221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4680 (or 4677 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 13513221 is about 3676.0333241145. The cubic root of 13513221 is about 238.1878621728.

Adding to 13513221 its reverse (12231531), we get a palindrome (25744752).

The spelling of 13513221 in words is "thirteen million, five hundred thirteen thousand, two hundred twenty-one".