2778791243 has 2 divisors, whose sum is σ = 2778791244. Its totient is φ = 2778791242.

The previous prime is 2778791233. The next prime is 2778791311. The reversal of 2778791243 is 3421978772.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2778791243 - 2⁴ = 2778791227 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 2778791191 and 2778791200.

It is not a weakly prime, because it can be changed into another prime (2778791233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1389395621 + 1389395622.

It is an arithmetic number, because the mean of its divisors is an integer number (1389395622).

Almost surely, 2^2778791243 is an apocalyptic number.

2778791243 is a deficient number, since it is larger than the sum of its proper divisors (1).

2778791243 is an equidigital number, since it uses as much as digits as its factorization.

2778791243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 50.

The square root of 2778791243 is about 52714.2413679643. The cubic root of 2778791243 is about 1405.8920459840.

The spelling of 2778791243 in words is "two billion, seven hundred seventy-eight million, seven hundred ninety-one thousand, two hundred forty-three".