13521553 has 4 divisors (see below), whose sum is σ = 13529268. Its totient is φ = 13513840.

The previous prime is 13521551. The next prime is 13521581. The reversal of 13521553 is 35512531.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 9290304 + 4231249 = 3048^2 + 2057^2 .

It is a cyclic number.

It is not a de Polignac number, because 13521553 - 2¹ = 13521551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13521551) 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, 183 + ... + 5203.

It is an arithmetic number, because the mean of its divisors is an integer number (3382317).

Almost surely, 2^13521553 is an apocalyptic number.

It is an amenable number.

13521553 is a deficient number, since it is larger than the sum of its proper divisors (7715).

13521553 is an equidigital number, since it uses as much as digits as its factorization.

13521553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7714.

The product of its digits is 2250, while the sum is 25.

The square root of 13521553 is about 3677.1664362658. The cubic root of 13521553 is about 238.2368061791.

The spelling of 13521553 in words is "thirteen million, five hundred twenty-one thousand, five hundred fifty-three".