2778656 has 24 divisors (see below), whose sum is σ = 5552064. Its totient is φ = 1368640.

The previous prime is 2778649. The next prime is 2778673. The reversal of 2778656 is 6568772.

2778656 = T₁₉₁ + T₁₉₂ + ... + T₂₈₆.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1661 + ... + 2883.

It is an arithmetic number, because the mean of its divisors is an integer number (231336).

2^2778656 is an apocalyptic number.

It is an amenable number.

2778656 is a deficient number, since it is larger than the sum of its proper divisors (2773408).

2778656 is a wasteful number, since it uses less digits than its factorization.

2778656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1304 (or 1296 counting only the distinct ones).

The product of its digits is 141120, while the sum is 41.

The square root of 2778656 is about 1666.9301125122. The cubic root of 2778656 is about 140.5869237488.

The spelling of 2778656 in words is "two million, seven hundred seventy-eight thousand, six hundred fifty-six".