13013521 has 4 divisors (see below), whose sum is σ = 13433344. Its totient is φ = 12593700.

The previous prime is 13013513. The next prime is 13013527. The reversal of 13013521 is 12531031.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12531031 = 1097 ⋅11423.

It is a cyclic number.

It is not a de Polignac number, because 13013521 - 2³ = 13013513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13013495 and 13013504.

It is not an unprimeable number, because it can be changed into a prime (13013527) 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, 209865 + ... + 209926.

It is an arithmetic number, because the mean of its divisors is an integer number (3358336).

Almost surely, 2^13013521 is an apocalyptic number.

It is an amenable number.

13013521 is a deficient number, since it is larger than the sum of its proper divisors (419823).

13013521 is an equidigital number, since it uses as much as digits as its factorization.

13013521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419822.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 13013521 is about 3607.4258135130. The cubic root of 13013521 is about 235.2149594913.

Adding to 13013521 its reverse (12531031), we get a palindrome (25544552).

The spelling of 13013521 in words is "thirteen million, thirteen thousand, five hundred twenty-one".