2640138888 has 64 divisors (see below), whose sum is σ = 6835046400. Its totient is φ = 848816640.

The previous prime is 2640138887. The next prime is 2640138899. The reversal of 2640138888 is 8888310462.

It is not an unprimeable number, because it can be changed into a prime (2640138883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1156308 + ... + 1158588.

It is an arithmetic number, because the mean of its divisors is an integer number (106797600).

Almost surely, 2^2640138888 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2640138888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3417523200).

2640138888 is an abundant number, since it is smaller than the sum of its proper divisors (4194907512).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2640138888 is a wasteful number, since it uses less digits than its factorization.

2640138888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3982 (or 3978 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 48.

The square root of 2640138888 is about 51382.2818489020. The cubic root of 2640138888 is about 1382.1088823162.

The spelling of 2640138888 in words is "two billion, six hundred forty million, one hundred thirty-eight thousand, eight hundred eighty-eight".