15225209 has 4 divisors (see below), whose sum is σ = 15252816. Its totient is φ = 15197604.

The previous prime is 15225181. The next prime is 15225233. The reversal of 15225209 is 90252251.

15225209 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 a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90252251 = 941 ⋅95911.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15225209 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (15225239) 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, 12959 + ... + 14084.

It is an arithmetic number, because the mean of its divisors is an integer number (3813204).

Almost surely, 2^15225209 is an apocalyptic number.

It is an amenable number.

15225209 is a deficient number, since it is larger than the sum of its proper divisors (27607).

15225209 is an equidigital number, since it uses as much as digits as its factorization.

15225209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27606.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 15225209 is about 3901.9493846025. The cubic root of 15225209 is about 247.8493329117.

The spelling of 15225209 in words is "fifteen million, two hundred twenty-five thousand, two hundred nine".