2638889 has 12 divisors (see below), whose sum is σ = 2941428. Its totient is φ = 2365440.

The previous prime is 2638879. The next prime is 2638897. The reversal of 2638889 is 9888362.

It can be written as a sum of positive squares in 2 ways, for example, as 267289 + 2371600 = 517^2 + 1540^2 .

It is not a de Polignac number, because 2638889 - 2⁴ = 2638873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2638849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13577 + ... + 13769.

It is an arithmetic number, because the mean of its divisors is an integer number (245119).

2^2638889 is an apocalyptic number.

It is an amenable number.

2638889 is a deficient number, since it is larger than the sum of its proper divisors (302539).

2638889 is a wasteful number, since it uses less digits than its factorization.

2638889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328 (or 317 counting only the distinct ones).

The product of its digits is 165888, while the sum is 44.

The square root of 2638889 is about 1624.4657583341. The cubic root of 2638889 is about 138.1890743037.

The spelling of 2638889 in words is "two million, six hundred thirty-eight thousand, eight hundred eighty-nine".