12660561 has 12 divisors (see below), whose sum is σ = 18459792. Its totient is φ = 8360856.

The previous prime is 12660553. The next prime is 12660569. The reversal of 12660561 is 16506621.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (12660553) and next prime (12660569).

It is not a de Polignac number, because 12660561 - 2³ = 12660553 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (12660569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5611 + ... + 7536.

It is an arithmetic number, because the mean of its divisors is an integer number (1538316).

Almost surely, 2^12660561 is an apocalyptic number.

It is an amenable number.

12660561 is a deficient number, since it is larger than the sum of its proper divisors (5799231).

12660561 is a wasteful number, since it uses less digits than its factorization.

12660561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13260 (or 13257 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 12660561 is about 3558.1682085028. The cubic root of 12660561 is about 233.0688947539.

The spelling of 12660561 in words is "twelve million, six hundred sixty thousand, five hundred sixty-one".