18023403 has 16 divisors (see below), whose sum is σ = 24803360. Its totient is φ = 11632896.

The previous prime is 18023393. The next prime is 18023429. The reversal of 18023403 is 30432081.

It is a happy number.

It is not a de Polignac number, because 18023403 - 2¹⁰ = 18022379 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18023403.

It is not an unprimeable number, because it can be changed into a prime (18023483) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43863 + ... + 44271.

It is an arithmetic number, because the mean of its divisors is an integer number (1550210).

Almost surely, 2^18023403 is an apocalyptic number.

18023403 is a deficient number, since it is larger than the sum of its proper divisors (6779957).

18023403 is a wasteful number, since it uses less digits than its factorization.

18023403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 18023403 is about 4245.3978612140. The cubic root of 18023403 is about 262.1876702522.

Adding to 18023403 its reverse (30432081), we get a palindrome (48455484).

The spelling of 18023403 in words is "eighteen million, twenty-three thousand, four hundred three".