2578861 has 2 divisors, whose sum is σ = 2578862. Its totient is φ = 2578860.

The previous prime is 2578847. The next prime is 2578879. The reversal of 2578861 is 1688752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2540836 + 38025 = 1594^2 + 195^2 .

It is a cyclic number.

It is not a de Polignac number, because 2578861 - 2⁷ = 2578733 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2578861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2578801) 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, 1289430 + 1289431.

It is an arithmetic number, because the mean of its divisors is an integer number (1289431).

2^2578861 is an apocalyptic number.

It is an amenable number.

2578861 is a deficient number, since it is larger than the sum of its proper divisors (1).

2578861 is an equidigital number, since it uses as much as digits as its factorization.

2578861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26880, while the sum is 37.

The square root of 2578861 is about 1605.8832460674. The cubic root of 2578861 is about 137.1332108687.

The spelling of 2578861 in words is "two million, five hundred seventy-eight thousand, eight hundred sixty-one".