18282521 has 2 divisors, whose sum is σ = 18282522. Its totient is φ = 18282520.

The previous prime is 18282487. The next prime is 18282527. The reversal of 18282521 is 12528281.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15523600 + 2758921 = 3940^2 + 1661^2 .

It is an emirp because it is prime and its reverse (12528281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18282521 - 2⁶ = 18282457 is a prime.

It is not a weakly prime, because it can be changed into another prime (18282527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9141260 + 9141261.

It is an arithmetic number, because the mean of its divisors is an integer number (9141261).

Almost surely, 2^18282521 is an apocalyptic number.

It is an amenable number.

18282521 is a deficient number, since it is larger than the sum of its proper divisors (1).

18282521 is an equidigital number, since it uses as much as digits as its factorization.

18282521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2560, while the sum is 29.

The square root of 18282521 is about 4275.8064736375. The cubic root of 18282521 is about 263.4381656352.

The spelling of 18282521 in words is "eighteen million, two hundred eighty-two thousand, five hundred twenty-one".