2564839 has 4 divisors (see below), whose sum is σ = 2571520. Its totient is φ = 2558160.

The previous prime is 2564831. The next prime is 2564843. The reversal of 2564839 is 9384652.

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

It is a cyclic number.

It is not a de Polignac number, because 2564839 - 2³ = 2564831 is a prime.

It is a d-powerful number, because it can be written as 2¹⁵ + 5⁹ + 6⁶ + 4⁴ + 8³ + 3¹² + 9² .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2564798 and 2564807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2564831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2727 + ... + 3544.

It is an arithmetic number, because the mean of its divisors is an integer number (642880).

2^2564839 is an apocalyptic number.

2564839 is a deficient number, since it is larger than the sum of its proper divisors (6681).

2564839 is an equidigital number, since it uses as much as digits as its factorization.

2564839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6680.

The product of its digits is 51840, while the sum is 37.

The square root of 2564839 is about 1601.5114735774. The cubic root of 2564839 is about 136.8842149575.

It can be divided in two parts, 2564 and 839, that added together give a triangular number (3403 = T₈₂).

The spelling of 2564839 in words is "two million, five hundred sixty-four thousand, eight hundred thirty-nine".