4208821 has 2 divisors, whose sum is σ = 4208822. Its totient is φ = 4208820.

The previous prime is 4208801. The next prime is 4208849. The reversal of 4208821 is 1288024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3591025 + 617796 = 1895^2 + 786^2 .

It is a cyclic number.

It is not a de Polignac number, because 4208821 - 2¹¹ = 4206773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4208801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2104410 + 2104411.

It is an arithmetic number, because the mean of its divisors is an integer number (2104411).

Almost surely, 2^4208821 is an apocalyptic number.

It is an amenable number.

4208821 is a deficient number, since it is larger than the sum of its proper divisors (1).

4208821 is an equidigital number, since it uses as much as digits as its factorization.

4208821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 4208821 is about 2051.5411280303. The cubic root of 4208821 is about 161.4557384289.

The spelling of 4208821 in words is "four million, two hundred eight thousand, eight hundred twenty-one".