2056621591 has 2 divisors, whose sum is σ = 2056621592. Its totient is φ = 2056621590.

The previous prime is 2056621513. The next prime is 2056621607. The reversal of 2056621591 is 1951266502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2056621591 - 2²⁵ = 2023067159 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2056621591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2056621991) 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, 1028310795 + 1028310796.

It is an arithmetic number, because the mean of its divisors is an integer number (1028310796).

Almost surely, 2^2056621591 is an apocalyptic number.

2056621591 is a deficient number, since it is larger than the sum of its proper divisors (1).

2056621591 is an equidigital number, since it uses as much as digits as its factorization.

2056621591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 2056621591 is about 45349.9899779482. The cubic root of 2056621591 is about 1271.7003679535.

The spelling of 2056621591 in words is "two billion, fifty-six million, six hundred twenty-one thousand, five hundred ninety-one".