2056565521 has 4 divisors (see below), whose sum is σ = 2056681012. Its totient is φ = 2056450032.

The previous prime is 2056565501. The next prime is 2056565527. The reversal of 2056565521 is 1255656502.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 563825025 + 1492740496 = 23745^2 + 38636^2 .

It is a cyclic number.

It is not a de Polignac number, because 2056565521 - 2⁹ = 2056565009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2056565527) 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, 24750 + ... + 68743.

It is an arithmetic number, because the mean of its divisors is an integer number (514170253).

Almost surely, 2^2056565521 is an apocalyptic number.

It is an amenable number.

2056565521 is a deficient number, since it is larger than the sum of its proper divisors (115491).

2056565521 is an equidigital number, since it uses as much as digits as its factorization.

2056565521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115490.

The product of its (nonzero) digits is 90000, while the sum is 37.

The square root of 2056565521 is about 45349.3717817568. The cubic root of 2056565521 is about 1271.6888109924.

The spelling of 2056565521 in words is "two billion, fifty-six million, five hundred sixty-five thousand, five hundred twenty-one".