56556561 has 4 divisors (see below), whose sum is σ = 75408752. Its totient is φ = 37704372.

The previous prime is 56556553. The next prime is 56556571. The reversal of 56556561 is 16565565.

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 not a de Polignac number, because 56556561 - 2³ = 56556553 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (56556571) 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, 9426091 + ... + 9426096.

It is an arithmetic number, because the mean of its divisors is an integer number (18852188).

Almost surely, 2^56556561 is an apocalyptic number.

It is an amenable number.

56556561 is a deficient number, since it is larger than the sum of its proper divisors (18852191).

56556561 is a wasteful number, since it uses less digits than its factorization.

56556561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18852190.

The product of its digits is 135000, while the sum is 39.

The square root of 56556561 is about 7520.4096298008. The cubic root of 56556561 is about 383.8495165022.

The spelling of 56556561 in words is "fifty-six million, five hundred fifty-six thousand, five hundred sixty-one".