2778765 has 24 divisors (see below), whose sum is σ = 4890144. Its totient is φ = 1346400.

The previous prime is 2778739. The next prime is 2778779. The reversal of 2778765 is 5678772.

2778765 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 2778765 - 2¹⁰ = 2777741 is a prime.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1050 + ... + 2580.

It is an arithmetic number, because the mean of its divisors is an integer number (203756).

2^2778765 is an apocalyptic number.

It is an amenable number.

2778765 is a deficient number, since it is larger than the sum of its proper divisors (2111379).

2778765 is a wasteful number, since it uses less digits than its factorization.

2778765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1561 (or 1550 counting only the distinct ones).

The product of its digits is 164640, while the sum is 42.

The square root of 2778765 is about 1666.9628070236. The cubic root of 2778765 is about 140.5887620206.

The spelling of 2778765 in words is "two million, seven hundred seventy-eight thousand, seven hundred sixty-five".