2644381885 has 16 divisors (see below), whose sum is σ = 3190570416. Its totient is φ = 2103994368.

The previous prime is 2644381853. The next prime is 2644381891. The reversal of 2644381885 is 5881834462.

It can be written as a sum of positive squares in 8 ways, for example, as 936543609 + 1707838276 = 30603^2 + 41326^2 .

It is a cyclic number.

It is not a de Polignac number, because 2644381885 - 2⁵ = 2644381853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 930687 + ... + 933523.

It is an arithmetic number, because the mean of its divisors is an integer number (199410651).

Almost surely, 2^2644381885 is an apocalyptic number.

It is an amenable number.

2644381885 is a deficient number, since it is larger than the sum of its proper divisors (546188531).

2644381885 is a wasteful number, since it uses less digits than its factorization.

2644381885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3792.

The product of its digits is 1474560, while the sum is 49.

The square root of 2644381885 is about 51423.5537959017. The cubic root of 2644381885 is about 1382.8488869615.

The spelling of 2644381885 in words is "two billion, six hundred forty-four million, three hundred eighty-one thousand, eight hundred eighty-five".