2138257872 has 120 divisors (see below), whose sum is σ = 6478097280. Its totient is φ = 675190080.

The previous prime is 2138257867. The next prime is 2138257873. The reversal of 2138257872 is 2787528312.

2138257872 is a `hidden beast` number, since 2 + 1 + 3 + 8 + 2 + 578 + 72 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2138257873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 149097 + ... + 162807.

It is an arithmetic number, because the mean of its divisors is an integer number (53984144).

Almost surely, 2^2138257872 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 2138257872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3239048640).

2138257872 is an abundant number, since it is smaller than the sum of its proper divisors (4339839408).

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

2138257872 is a wasteful number, since it uses less digits than its factorization.

2138257872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13766 (or 13735 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 2138257872 is about 46241.3005007428. The cubic root of 2138257872 is about 1288.3089578135.

The spelling of 2138257872 in words is "two billion, one hundred thirty-eight million, two hundred fifty-seven thousand, eight hundred seventy-two".