2821860 has 72 divisors (see below), whose sum is σ = 8733816. Its totient is φ = 737280.

The previous prime is 2821859. The next prime is 2821867. The reversal of 2821860 is 681282.

2821860 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 331776 + 2490084 = 576^2 + 1578^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2821867) 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 23 ways as a sum of consecutive naturals, for example, 10852 + ... + 11108.

It is an arithmetic number, because the mean of its divisors is an integer number (121303).

2^2821860 is an apocalyptic number.

2821860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2821860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4366908).

2821860 is an abundant number, since it is smaller than the sum of its proper divisors (5911956).

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

2821860 is a wasteful number, since it uses less digits than its factorization.

2821860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333 (or 328 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 2821860 is about 1679.8392780263. The cubic root of 2821860 is about 141.3118193391.

The spelling of 2821860 in words is "two million, eight hundred twenty-one thousand, eight hundred sixty".