13013221 has 4 divisors (see below), whose sum is σ = 14014252. Its totient is φ = 12012192.

The previous prime is 13013197. The next prime is 13013227. The reversal of 13013221 is 12231031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12231031 = 163 ⋅75037.

It can be written as a sum of positive squares in 2 ways, for example, as 6708100 + 6305121 = 2590^2 + 2511^2 .

It is a cyclic number.

It is not a de Polignac number, because 13013221 - 2⁹ = 13012709 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 1001017 = 13013221 / (1 + 3 + 0 + 1 + 3 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13013227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 500496 + ... + 500521.

It is an arithmetic number, because the mean of its divisors is an integer number (3503563).

Almost surely, 2^13013221 is an apocalyptic number.

It is an amenable number.

13013221 is a deficient number, since it is larger than the sum of its proper divisors (1001031).

13013221 is a wasteful number, since it uses less digits than its factorization.

13013221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001030.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 13013221 is about 3607.3842323767. The cubic root of 13013221 is about 235.2131520115.

Adding to 13013221 its reverse (12231031), we get a palindrome (25244252).

The spelling of 13013221 in words is "thirteen million, thirteen thousand, two hundred twenty-one".