2104821 has 12 divisors (see below), whose sum is σ = 3219372. Its totient is φ = 1320576.

The previous prime is 2104811. The next prime is 2104841. The reversal of 2104821 is 1284012.

2104821 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 2 ways, for example, as 756900 + 1347921 = 870^2 + 1161^2 .

It is not a de Polignac number, because 2104821 - 2⁶ = 2104757 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2104794 and 2104803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2104811) 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 11 ways as a sum of consecutive naturals, for example, 6726 + ... + 7031.

It is an arithmetic number, because the mean of its divisors is an integer number (268281).

2^2104821 is an apocalyptic number.

It is an amenable number.

2104821 is a deficient number, since it is larger than the sum of its proper divisors (1114551).

2104821 is a wasteful number, since it uses less digits than its factorization.

2104821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13780 (or 13777 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 2104821 is about 1450.8001240695. The cubic root of 2104821 is about 128.1558364010.

Adding to 2104821 its reverse (1284012), we get a palindrome (3388833).

The spelling of 2104821 in words is "two million, one hundred four thousand, eight hundred twenty-one".