8523821 has 2 divisors, whose sum is σ = 8523822. Its totient is φ = 8523820.

The previous prime is 8523793. The next prime is 8523841. The reversal of 8523821 is 1283258.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5244100 + 3279721 = 2290^2 + 1811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8523821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8523841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4261910 + 4261911.

It is an arithmetic number, because the mean of its divisors is an integer number (4261911).

Almost surely, 2^8523821 is an apocalyptic number.

It is an amenable number.

8523821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8523821 is an equidigital number, since it uses as much as digits as its factorization.

8523821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3840, while the sum is 29.

The square root of 8523821 is about 2919.5583570122. The cubic root of 8523821 is about 204.2732225862.

The spelling of 8523821 in words is "eight million, five hundred twenty-three thousand, eight hundred twenty-one".