18243823 has 4 divisors (see below), whose sum is σ = 19647208. Its totient is φ = 16840440.

The previous prime is 18243793. The next prime is 18243829. The reversal of 18243823 is 32834281.

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 18243823 - 2²¹ = 16146671 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 (18243829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 701673 + ... + 701698.

It is an arithmetic number, because the mean of its divisors is an integer number (4911802).

Almost surely, 2^18243823 is an apocalyptic number.

18243823 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

18243823 is a deficient number, since it is larger than the sum of its proper divisors (1403385).

18243823 is a wasteful number, since it uses less digits than its factorization.

18243823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1403384.

The product of its digits is 9216, while the sum is 31.

The square root of 18243823 is about 4271.2788483076. The cubic root of 18243823 is about 263.2521640910.

The spelling of 18243823 in words is "eighteen million, two hundred forty-three thousand, eight hundred twenty-three".