15315609 has 4 divisors (see below), whose sum is σ = 20420816. Its totient is φ = 10210404.

The previous prime is 15315593. The next prime is 15315647. The reversal of 15315609 is 90651351.

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.

It is not a de Polignac number, because 15315609 - 2⁴ = 15315593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15315649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2552599 + ... + 2552604.

It is an arithmetic number, because the mean of its divisors is an integer number (5105204).

Almost surely, 2^15315609 is an apocalyptic number.

It is an amenable number.

15315609 is a deficient number, since it is larger than the sum of its proper divisors (5105207).

15315609 is an equidigital number, since it uses as much as digits as its factorization.

15315609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5105206.

The product of its (nonzero) digits is 4050, while the sum is 30.

The square root of 15315609 is about 3913.5161939105. The cubic root of 15315609 is about 248.3389021268.

It can be divided in two parts, 1531 and 5609, that added together give a triangular number (7140 = T₁₁₉).

The spelling of 15315609 in words is "fifteen million, three hundred fifteen thousand, six hundred nine".