13043521 has 4 divisors (see below), whose sum is σ = 13094532. Its totient is φ = 12992512.

The previous prime is 13043497. The next prime is 13043561. The reversal of 13043521 is 12534031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12534031 = 1663 ⋅7537.

It can be written as a sum of positive squares in 2 ways, for example, as 12503296 + 540225 = 3536^2 + 735^2 .

It is a cyclic number.

It is not a de Polignac number, because 13043521 - 2⁵ = 13043489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13043561) 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, 25120 + ... + 25633.

It is an arithmetic number, because the mean of its divisors is an integer number (3273633).

Almost surely, 2^13043521 is an apocalyptic number.

It is an amenable number.

13043521 is a deficient number, since it is larger than the sum of its proper divisors (51011).

13043521 is an equidigital number, since it uses as much as digits as its factorization.

13043521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51010.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 13043521 is about 3611.5815095329. The cubic root of 13043521 is about 235.3955673714.

Adding to 13043521 its reverse (12534031), we get a palindrome (25577552).

The spelling of 13043521 in words is "thirteen million, forty-three thousand, five hundred twenty-one".