2560639 has 2 divisors, whose sum is σ = 2560640. Its totient is φ = 2560638.

The previous prime is 2560637. The next prime is 2560651. The reversal of 2560639 is 9360652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2560639 - 2¹ = 2560637 is a prime.

Together with 2560637, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2560639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2560637) 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 as a sum of consecutive naturals, namely, 1280319 + 1280320.

It is an arithmetic number, because the mean of its divisors is an integer number (1280320).

2^2560639 is an apocalyptic number.

2560639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2560639 is an equidigital number, since it uses as much as digits as its factorization.

2560639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 31.

The square root of 2560639 is about 1600.1996750406. The cubic root of 2560639 is about 136.8094568146.

The spelling of 2560639 in words is "two million, five hundred sixty thousand, six hundred thirty-nine".