2778564 has 12 divisors (see below), whose sum is σ = 6483344. Its totient is φ = 926184.

The previous prime is 2778547. The next prime is 2778583. The reversal of 2778564 is 4658772.

It is a tau number, because it is divible by the number of its divisors (12).

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, 115762 + ... + 115785.

2^2778564 is an apocalyptic number.

It is an amenable number.

2778564 is an abundant number, since it is smaller than the sum of its proper divisors (3704780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2778564 is a wasteful number, since it uses less digits than its factorization.

2778564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231554 (or 231552 counting only the distinct ones).

The product of its digits is 94080, while the sum is 39.

The square root of 2778564 is about 1666.9025166458. The cubic root of 2778564 is about 140.5853721426.

The spelling of 2778564 in words is "two million, seven hundred seventy-eight thousand, five hundred sixty-four".