2778520 has 16 divisors (see below), whose sum is σ = 6251760. Its totient is φ = 1111392.

The previous prime is 2778481. The next prime is 2778521. The reversal of 2778520 is 258772.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2778521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34692 + ... + 34771.

It is an arithmetic number, because the mean of its divisors is an integer number (390735).

2^2778520 is an apocalyptic number.

2778520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2778520 is an abundant number, since it is smaller than the sum of its proper divisors (3473240).

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

2778520 is a wasteful number, since it uses less digits than its factorization.

2778520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69474 (or 69470 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 2778520 is about 1666.8893184612. The cubic root of 2778520 is about 140.5846300580.

The spelling of 2778520 in words is "two million, seven hundred seventy-eight thousand, five hundred twenty".