12885561 has 24 divisors (see below), whose sum is σ = 20791680. Its totient is φ = 7927632.

The previous prime is 12885557. The next prime is 12885569. The reversal of 12885561 is 16558821.

12885561 is a `hidden beast` number, since 12 + 8 + 85 + 561 = 666.

12885561 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12885561 - 2² = 12885557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12885569) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1120 + ... + 5198.

It is an arithmetic number, because the mean of its divisors is an integer number (866320).

Almost surely, 2^12885561 is an apocalyptic number.

It is an amenable number.

12885561 is a deficient number, since it is larger than the sum of its proper divisors (7906119).

12885561 is an equidigital number, since it uses as much as digits as its factorization.

12885561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4107 (or 4095 counting only the distinct ones).

The product of its digits is 19200, while the sum is 36.

The square root of 12885561 is about 3589.6463614122. The cubic root of 12885561 is about 234.4414742646.

The spelling of 12885561 in words is "twelve million, eight hundred eighty-five thousand, five hundred sixty-one".