6591439649 has 4 divisors (see below), whose sum is σ = 6591982740. Its totient is φ = 6590896560.

The previous prime is 6591439643. The next prime is 6591439651. The reversal of 6591439649 is 9469341956.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5956752400 + 634687249 = 77180^2 + 25193^2 .

It is a cyclic number.

It is not a de Polignac number, because 6591439649 - 2¹² = 6591435553 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6591439594 and 6591439603.

It is not an unprimeable number, because it can be changed into a prime (6591439643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252914 + ... + 277755.

It is an arithmetic number, because the mean of its divisors is an integer number (1647995685).

Almost surely, 2^6591439649 is an apocalyptic number.

It is an amenable number.

6591439649 is a deficient number, since it is larger than the sum of its proper divisors (543091).

6591439649 is a wasteful number, since it uses less digits than its factorization.

6591439649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543090.

The product of its digits is 6298560, while the sum is 56.

The square root of 6591439649 is about 81187.6816333611. The cubic root of 6591439649 is about 1874.9661290711.

The spelling of 6591439649 in words is "six billion, five hundred ninety-one million, four hundred thirty-nine thousand, six hundred forty-nine".