2564638 has 16 divisors (see below), whose sum is σ = 4055040. Its totient is φ = 1214136.

The previous prime is 2564633. The next prime is 2564651. The reversal of 2564638 is 8364652.

It is a happy number.

It is a d-powerful number, because it can be written as 2¹⁹ + 5⁹ + 6³ + 4⁵ + 6⁶ + 3⁸ + 8⁵ .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2564633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5623 + ... + 6061.

It is an arithmetic number, because the mean of its divisors is an integer number (253440).

2^2564638 is an apocalyptic number.

2564638 is a deficient number, since it is larger than the sum of its proper divisors (1490402).

2564638 is a wasteful number, since it uses less digits than its factorization.

2564638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591.

The product of its digits is 34560, while the sum is 34.

The square root of 2564638 is about 1601.4487191290. The cubic root of 2564638 is about 136.8806391066.

The spelling of 2564638 in words is "two million, five hundred sixty-four thousand, six hundred thirty-eight".