56784445561 has 2 divisors, whose sum is σ = 56784445562. Its totient is φ = 56784445560.

The previous prime is 56784445559. The next prime is 56784445603. The reversal of 56784445561 is 16554448765.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30780948025 + 26003497536 = 175445^2 + 161256^2 .

It is a cyclic number.

It is not a de Polignac number, because 56784445561 - 2¹ = 56784445559 is a prime.

Together with 56784445559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (56784445261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28392222780 + 28392222781.

It is an arithmetic number, because the mean of its divisors is an integer number (28392222781).

Almost surely, 2^56784445561 is an apocalyptic number.

It is an amenable number.

56784445561 is a deficient number, since it is larger than the sum of its proper divisors (1).

56784445561 is an equidigital number, since it uses as much as digits as its factorization.

56784445561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128000, while the sum is 55.

The spelling of 56784445561 in words is "fifty-six billion, seven hundred eighty-four million, four hundred forty-five thousand, five hundred sixty-one".