2781238811 has 32 divisors (see below), whose sum is σ = 3286660608. Its totient is φ = 2329067520.

The previous prime is 2781238799. The next prime is 2781238847. The reversal of 2781238811 is 1188321872.

2781238811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2781238811 - 2²² = 2777044507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2781238871) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2143715 + ... + 2145011.

It is an arithmetic number, because the mean of its divisors is an integer number (102708144).

Almost surely, 2^2781238811 is an apocalyptic number.

2781238811 is a deficient number, since it is larger than the sum of its proper divisors (505421797).

2781238811 is a wasteful number, since it uses less digits than its factorization.

2781238811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1671.

The product of its digits is 43008, while the sum is 41.

The square root of 2781238811 is about 52737.4516923220. The cubic root of 2781238811 is about 1406.3046962205.

The spelling of 2781238811 in words is "two billion, seven hundred eighty-one million, two hundred thirty-eight thousand, eight hundred eleven".