2778311825 has 6 divisors (see below), whose sum is σ = 3445106694. Its totient is φ = 2222649440.

The previous prime is 2778311777. The next prime is 2778311827. The reversal of 2778311825 is 5281138772.

It can be written as a sum of positive squares in 3 ways, for example, as 155950144 + 2622361681 = 12488^2 + 51209^2 .

It is a de Polignac number, because none of the positive numbers 2^k-2778311825 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2778311827) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55566212 + ... + 55566261.

It is an arithmetic number, because the mean of its divisors is an integer number (574184449).

Almost surely, 2^2778311825 is an apocalyptic number.

2778311825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2778311825 is a deficient number, since it is larger than the sum of its proper divisors (666794869).

2778311825 is a wasteful number, since it uses less digits than its factorization.

2778311825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111132483 (or 111132478 counting only the distinct ones).

The product of its digits is 188160, while the sum is 44.

The square root of 2778311825 is about 52709.6938427838. The cubic root of 2778311825 is about 1405.8111896380.

The spelling of 2778311825 in words is "two billion, seven hundred seventy-eight million, three hundred eleven thousand, eight hundred twenty-five".