12553661 has 4 divisors (see below), whose sum is σ = 13214400. Its totient is φ = 11892924.

The previous prime is 12553657. The next prime is 12553669. The reversal of 12553661 is 16635521.

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 12553661 - 2² = 12553657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12553669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 330341 + ... + 330378.

It is an arithmetic number, because the mean of its divisors is an integer number (3303600).

Almost surely, 2^12553661 is an apocalyptic number.

It is an amenable number.

12553661 is a deficient number, since it is larger than the sum of its proper divisors (660739).

12553661 is an equidigital number, since it uses as much as digits as its factorization.

12553661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660738.

The product of its digits is 5400, while the sum is 29.

The square root of 12553661 is about 3543.1145903005. The cubic root of 12553661 is about 232.4110639920.

The spelling of 12553661 in words is "twelve million, five hundred fifty-three thousand, six hundred sixty-one".