12240209 has 4 divisors (see below), whose sum is σ = 12772416. Its totient is φ = 11708004.

The previous prime is 12240203. The next prime is 12240223. The reversal of 12240209 is 90204221.

12240209 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: 90204221 = 8117 ⋅11113.

It is a cyclic number.

It is not a de Polignac number, because 12240209 - 2¹² = 12236113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12240203) 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, 266069 + ... + 266114.

It is an arithmetic number, because the mean of its divisors is an integer number (3193104).

Almost surely, 2^12240209 is an apocalyptic number.

It is an amenable number.

12240209 is a deficient number, since it is larger than the sum of its proper divisors (532207).

12240209 is an equidigital number, since it uses as much as digits as its factorization.

12240209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532206.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 12240209 is about 3498.6010061166. The cubic root of 12240209 is about 230.4603822035.

The spelling of 12240209 in words is "twelve million, two hundred forty thousand, two hundred nine".