56684005621 has 2 divisors, whose sum is σ = 56684005622. Its totient is φ = 56684005620.

The previous prime is 56684005619. The next prime is 56684005639. The reversal of 56684005621 is 12650048665.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47930344900 + 8753660721 = 218930^2 + 93561^2 .

It is a cyclic number.

It is not a de Polignac number, because 56684005621 - 2¹ = 56684005619 is a prime.

Together with 56684005619, 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 (56684005691) 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 as a sum of consecutive naturals, namely, 28342002810 + 28342002811.

It is an arithmetic number, because the mean of its divisors is an integer number (28342002811).

Almost surely, 2^56684005621 is an apocalyptic number.

It is an amenable number.

56684005621 is a deficient number, since it is larger than the sum of its proper divisors (1).

56684005621 is an equidigital number, since it uses as much as digits as its factorization.

56684005621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 345600, while the sum is 43.

The spelling of 56684005621 in words is "fifty-six billion, six hundred eighty-four million, five thousand, six hundred twenty-one".