2139475878 has 24 divisors (see below), whose sum is σ = 4637265048. Its totient is φ = 712891872.

The previous prime is 2139475859. The next prime is 2139475883. The reversal of 2139475878 is 8785749312.

It is a happy number.

2139475878 is a `hidden beast` number, since 2 + 13 + 9 + 47 + 587 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30625 + ... + 72227.

It is an arithmetic number, because the mean of its divisors is an integer number (193219377).

Almost surely, 2^2139475878 is an apocalyptic number.

2139475878 is an abundant number, since it is smaller than the sum of its proper divisors (2497789170).

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

2139475878 is a wasteful number, since it uses less digits than its factorization.

2139475878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44468 (or 44465 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The square root of 2139475878 is about 46254.4687354638. The cubic root of 2139475878 is about 1288.5535292173.

The spelling of 2139475878 in words is "two billion, one hundred thirty-nine million, four hundred seventy-five thousand, eight hundred seventy-eight".