18020287 has 4 divisors (see below), whose sum is σ = 18052096. Its totient is φ = 17988480.

The previous prime is 18020267. The next prime is 18020309. The reversal of 18020287 is 78202081.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18020287 - 2¹¹ = 18018239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18020267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15039 + ... + 16192.

It is an arithmetic number, because the mean of its divisors is an integer number (4513024).

Almost surely, 2^18020287 is an apocalyptic number.

18020287 is a deficient number, since it is larger than the sum of its proper divisors (31809).

18020287 is an equidigital number, since it uses as much as digits as its factorization.

18020287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31808.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 18020287 is about 4245.0308597229. The cubic root of 18020287 is about 262.1725598267.

The spelling of 18020287 in words is "eighteen million, twenty thousand, two hundred eighty-seven".