3021821 has 4 divisors (see below), whose sum is σ = 3296544. Its totient is φ = 2747100.

The previous prime is 3021797. The next prime is 3021833. The reversal of 3021821 is 1281203.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3021821 - 2¹⁸ = 2759677 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3021821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3021871) 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, 137345 + ... + 137366.

It is an arithmetic number, because the mean of its divisors is an integer number (824136).

Almost surely, 2^3021821 is an apocalyptic number.

It is an amenable number.

3021821 is a deficient number, since it is larger than the sum of its proper divisors (274723).

3021821 is a wasteful number, since it uses less digits than its factorization.

3021821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274722.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 3021821 is about 1738.3385746166. The cubic root of 3021821 is about 144.5737940390.

The spelling of 3021821 in words is "three million, twenty-one thousand, eight hundred twenty-one".