12556109 has 4 divisors (see below), whose sum is σ = 12655104. Its totient is φ = 12457116.

The previous prime is 12556099. The next prime is 12556111. The reversal of 12556109 is 90165521.

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 a cyclic number.

It is not a de Polignac number, because 12556109 - 2²⁰ = 11507533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12556139) 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, 49307 + ... + 49560.

It is an arithmetic number, because the mean of its divisors is an integer number (3163776).

Almost surely, 2^12556109 is an apocalyptic number.

It is an amenable number.

12556109 is a deficient number, since it is larger than the sum of its proper divisors (98995).

12556109 is an equidigital number, since it uses as much as digits as its factorization.

12556109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98994.

The product of its (nonzero) digits is 2700, while the sum is 29.

The square root of 12556109 is about 3543.4600322284. The cubic root of 12556109 is about 232.4261699521.

The spelling of 12556109 in words is "twelve million, five hundred fifty-six thousand, one hundred nine".