18024821 has 2 divisors, whose sum is σ = 18024822. Its totient is φ = 18024820.

The previous prime is 18024793. The next prime is 18024827. The reversal of 18024821 is 12842081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14546596 + 3478225 = 3814^2 + 1865^2 .

It is a cyclic number.

It is not a de Polignac number, because 18024821 - 2¹⁸ = 17762677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18024827) 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 as a sum of consecutive naturals, namely, 9012410 + 9012411.

It is an arithmetic number, because the mean of its divisors is an integer number (9012411).

Almost surely, 2^18024821 is an apocalyptic number.

It is an amenable number.

18024821 is a deficient number, since it is larger than the sum of its proper divisors (1).

18024821 is an equidigital number, since it uses as much as digits as its factorization.

18024821 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 26.

The square root of 18024821 is about 4245.5648623004. The cubic root of 18024821 is about 262.1945459860.

The spelling of 18024821 in words is "eighteen million, twenty-four thousand, eight hundred twenty-one".