13525609 has 4 divisors (see below), whose sum is σ = 13891204. Its totient is φ = 13160016.

The previous prime is 13525601. The next prime is 13525639. The reversal of 13525609 is 90652531.

13525609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90652531 = 571 ⋅158761.

It can be written as a sum of positive squares in 2 ways, for example, as 12531600 + 994009 = 3540^2 + 997^2 .

It is a cyclic number.

It is not a de Polignac number, because 13525609 - 2³ = 13525601 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (13525601) 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, 182742 + ... + 182815.

It is an arithmetic number, because the mean of its divisors is an integer number (3472801).

Almost surely, 2^13525609 is an apocalyptic number.

It is an amenable number.

13525609 is a deficient number, since it is larger than the sum of its proper divisors (365595).

13525609 is an equidigital number, since it uses as much as digits as its factorization.

13525609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365594.

The product of its (nonzero) digits is 8100, while the sum is 31.

The square root of 13525609 is about 3677.7179065284. The cubic root of 13525609 is about 238.2606247420.

It can be divided in two parts, 1352560 and 9, that added together give a square (1352569 = 1163²).

The spelling of 13525609 in words is "thirteen million, five hundred twenty-five thousand, six hundred nine".