12261209 has 4 divisors (see below), whose sum is σ = 12316416. Its totient is φ = 12206004.

The previous prime is 12261187. The next prime is 12261211. The reversal of 12261209 is 90216221.

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: 90216221 = 71 ⋅1270651.

It is a cyclic number.

It is not a de Polignac number, because 12261209 - 2⁸ = 12260953 is a prime.

It is a super-2 number, since 2×12261209² = 300674492283362, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12261259) 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, 27269 + ... + 27714.

It is an arithmetic number, because the mean of its divisors is an integer number (3079104).

Almost surely, 2^12261209 is an apocalyptic number.

It is an amenable number.

12261209 is a deficient number, since it is larger than the sum of its proper divisors (55207).

12261209 is an equidigital number, since it uses as much as digits as its factorization.

12261209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55206.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 12261209 is about 3501.6009195795. The cubic root of 12261209 is about 230.5921038902.

The spelling of 12261209 in words is "twelve million, two hundred sixty-one thousand, two hundred nine".