2181798278 has 16 divisors (see below), whose sum is σ = 3598331904. Its totient is φ = 983916360.

The previous prime is 2181798217. The next prime is 2181798299. The reversal of 2181798278 is 8728971812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 387650 + ... + 393237.

It is an arithmetic number, because the mean of its divisors is an integer number (224895744).

Almost surely, 2^2181798278 is an apocalyptic number.

2181798278 is a deficient number, since it is larger than the sum of its proper divisors (1416533626).

2181798278 is a wasteful number, since it uses less digits than its factorization.

2181798278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781027.

The product of its digits is 903168, while the sum is 53.

The square root of 2181798278 is about 46709.7235915607. The cubic root of 2181798278 is about 1296.9946904914.

The spelling of 2181798278 in words is "two billion, one hundred eighty-one million, seven hundred ninety-eight thousand, two hundred seventy-eight".