2781816 has 32 divisors (see below), whose sum is σ = 7180800. Its totient is φ = 897120.

The previous prime is 2781803. The next prime is 2781817. The reversal of 2781816 is 6181872.

It is a happy number.

2781816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2781817) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1126 + ... + 2613.

It is an arithmetic number, because the mean of its divisors is an integer number (224400).

2^2781816 is an apocalyptic number.

It is an amenable number.

2781816 is an abundant number, since it is smaller than the sum of its proper divisors (4398984).

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

2781816 is a wasteful number, since it uses less digits than its factorization.

2781816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3779 (or 3775 counting only the distinct ones).

The product of its digits is 5376, while the sum is 33.

The square root of 2781816 is about 1667.8776933576. The cubic root of 2781816 is about 140.6401972712.

The spelling of 2781816 in words is "two million, seven hundred eighty-one thousand, eight hundred sixteen".