2781620 has 24 divisors (see below), whose sum is σ = 6096384. Its totient is φ = 1064096.

The previous prime is 2781617. The next prime is 2781629. The reversal of 2781620 is 261872.

2781620 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 2781620.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2781629) 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, 2564 + ... + 3483.

It is an arithmetic number, because the mean of its divisors is an integer number (254016).

2^2781620 is an apocalyptic number.

2781620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2781620 is an abundant number, since it is smaller than the sum of its proper divisors (3314764).

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

2781620 is a wasteful number, since it uses less digits than its factorization.

2781620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6079 (or 6077 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 2781620 is about 1667.8189350166. The cubic root of 2781620 is about 140.6368941380.

The spelling of 2781620 in words is "two million, seven hundred eighty-one thousand, six hundred twenty".