12660509 has 4 divisors (see below), whose sum is σ = 12669504. Its totient is φ = 12651516.

The previous prime is 12660467. The next prime is 12660523. The reversal of 12660509 is 90506621.

12660509 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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 90506621 = 4001 ⋅22621.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12660509 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 (12660569) 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, 1877 + ... + 5370.

It is an arithmetic number, because the mean of its divisors is an integer number (3167376).

Almost surely, 2^12660509 is an apocalyptic number.

It is an amenable number.

12660509 is a deficient number, since it is larger than the sum of its proper divisors (8995).

12660509 is an equidigital number, since it uses as much as digits as its factorization.

12660509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8994.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 12660509 is about 3558.1609013646. The cubic root of 12660509 is about 233.0685756632.

The spelling of 12660509 in words is "twelve million, six hundred sixty thousand, five hundred nine".