56581806643 has 2 divisors, whose sum is σ = 56581806644. Its totient is φ = 56581806642.

The previous prime is 56581806553. The next prime is 56581806647. The reversal of 56581806643 is 34660818565.

56581806643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56581806643 is a prime.

It is not a weakly prime, because it can be changed into another prime (56581806647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28290903321 + 28290903322.

It is an arithmetic number, because the mean of its divisors is an integer number (28290903322).

Almost surely, 2^56581806643 is an apocalyptic number.

56581806643 is a deficient number, since it is larger than the sum of its proper divisors (1).

56581806643 is an equidigital number, since it uses as much as digits as its factorization.

56581806643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4147200, while the sum is 52.

The spelling of 56581806643 in words is "fifty-six billion, five hundred eighty-one million, eight hundred six thousand, six hundred forty-three".