18268281 has 16 divisors (see below), whose sum is σ = 27227520. Its totient is φ = 12105360.

The previous prime is 18268277. The next prime is 18268303. The reversal of 18268281 is 18286281.

It is not a de Polignac number, because 18268281 - 2² = 18268277 is a prime.

It is a super-2 number, since 2×18268281² = 667460181389922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18268241) 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 in 15 ways as a sum of consecutive naturals, for example, 2716 + ... + 6626.

It is an arithmetic number, because the mean of its divisors is an integer number (1701720).

Almost surely, 2^18268281 is an apocalyptic number.

It is an amenable number.

18268281 is a deficient number, since it is larger than the sum of its proper divisors (8959239).

18268281 is a wasteful number, since it uses less digits than its factorization.

18268281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4093 (or 4087 counting only the distinct ones).

The product of its digits is 12288, while the sum is 36.

The square root of 18268281 is about 4274.1409663229. The cubic root of 18268281 is about 263.3697517685.

The spelling of 18268281 in words is "eighteen million, two hundred sixty-eight thousand, two hundred eighty-one".