2778342785 has 4 divisors (see below), whose sum is σ = 3334011348. Its totient is φ = 2222674224.

The previous prime is 2778342781. The next prime is 2778342803. The reversal of 2778342785 is 5872438772.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2020772209 + 757570576 = 44953^2 + 27524^2 .

It is a cyclic number.

It is not a de Polignac number, because 2778342785 - 2² = 2778342781 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2778342781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 277834274 + ... + 277834283.

It is an arithmetic number, because the mean of its divisors is an integer number (833502837).

Almost surely, 2^2778342785 is an apocalyptic number.

It is an amenable number.

2778342785 is a deficient number, since it is larger than the sum of its proper divisors (555668563).

2778342785 is an equidigital number, since it uses as much as digits as its factorization.

2778342785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555668562.

The product of its digits is 5268480, while the sum is 53.

The square root of 2778342785 is about 52709.9875260847. The cubic root of 2778342785 is about 1405.8164114844.

The spelling of 2778342785 in words is "two billion, seven hundred seventy-eight million, three hundred forty-two thousand, seven hundred eighty-five".