2204821 has 2 divisors, whose sum is σ = 2204822. Its totient is φ = 2204820.

The previous prime is 2204809. The next prime is 2204827. The reversal of 2204821 is 1284022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1473796 + 731025 = 1214^2 + 855^2 .

It is a cyclic number.

It is not a de Polignac number, because 2204821 - 2⁵ = 2204789 is a prime.

It is a super-2 number, since 2×2204821² = 9722471284082, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2204827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1102410 + 1102411.

It is an arithmetic number, because the mean of its divisors is an integer number (1102411).

2^2204821 is an apocalyptic number.

It is an amenable number.

2204821 is a deficient number, since it is larger than the sum of its proper divisors (1).

2204821 is an equidigital number, since it uses as much as digits as its factorization.

2204821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 2204821 is about 1484.8639668333. The cubic root of 2204821 is about 130.1540776681.

Adding to 2204821 its reverse (1284022), we get a palindrome (3488843).

It can be divided in two parts, 2204 and 821, that added together give a square (3025 = 55²).

The spelling of 2204821 in words is "two million, two hundred four thousand, eight hundred twenty-one".