6391510561 has 2 divisors, whose sum is σ = 6391510562. Its totient is φ = 6391510560.

The previous prime is 6391510487. The next prime is 6391510637. The reversal of 6391510561 is 1650151936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3726369936 + 2665140625 = 61044^2 + 51625^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6391510561 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6391510561.

It is not a weakly prime, because it can be changed into another prime (6391516561) 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, 3195755280 + 3195755281.

It is an arithmetic number, because the mean of its divisors is an integer number (3195755281).

Almost surely, 2^6391510561 is an apocalyptic number.

It is an amenable number.

6391510561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6391510561 is an equidigital number, since it uses as much as digits as its factorization.

6391510561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24300, while the sum is 37.

The square root of 6391510561 is about 79946.9233992153. The cubic root of 6391510561 is about 1855.8142434214.

The spelling of 6391510561 in words is "six billion, three hundred ninety-one million, five hundred ten thousand, five hundred sixty-one".