18233813 has 8 divisors (see below), whose sum is σ = 19691448. Its totient is φ = 16784064.

The previous prime is 18233801. The next prime is 18233821. The reversal of 18233813 is 31833281.

It can be written as a sum of positive squares in 4 ways, for example, as 3541924 + 14691889 = 1882^2 + 3833^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18233813 - 2⁸ = 18233557 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 (18233213) 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 7 ways as a sum of consecutive naturals, for example, 3395 + ... + 6927.

It is an arithmetic number, because the mean of its divisors is an integer number (2461431).

Almost surely, 2^18233813 is an apocalyptic number.

18233813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18233813 is a deficient number, since it is larger than the sum of its proper divisors (1457635).

18233813 is a wasteful number, since it uses less digits than its factorization.

18233813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3943.

The product of its digits is 3456, while the sum is 29.

The square root of 18233813 is about 4270.1069073268. The cubic root of 18233813 is about 263.2040083169.

The spelling of 18233813 in words is "eighteen million, two hundred thirty-three thousand, eight hundred thirteen".