56661559 has 2 divisors, whose sum is σ = 56661560. Its totient is φ = 56661558.

The previous prime is 56661557. The next prime is 56661569. The reversal of 56661559 is 95516665.

56661559 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 56661559 - 2¹ = 56661557 is a prime.

Together with 56661557, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56661557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28330779 + 28330780.

It is an arithmetic number, because the mean of its divisors is an integer number (28330780).

Almost surely, 2^56661559 is an apocalyptic number.

56661559 is a deficient number, since it is larger than the sum of its proper divisors (1).

56661559 is an equidigital number, since it uses as much as digits as its factorization.

56661559 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 243000, while the sum is 43.

The square root of 56661559 is about 7527.3872625234. The cubic root of 56661559 is about 384.0869102147.

It can be divided in two parts, 5666 and 1559, that added together give a square (7225 = 85²).

The spelling of 56661559 in words is "fifty-six million, six hundred sixty-one thousand, five hundred fifty-nine".