18011903 has 8 divisors (see below), whose sum is σ = 22168608. Its totient is φ = 14251104.

The previous prime is 18011893. The next prime is 18011941. The reversal of 18011903 is 30911081.

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

It is not a de Polignac number, because 18011903 - 2⁴ = 18011887 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18011303) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98876 + ... + 99057.

It is an arithmetic number, because the mean of its divisors is an integer number (2771076).

Almost surely, 2^18011903 is an apocalyptic number.

18011903 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

18011903 is a deficient number, since it is larger than the sum of its proper divisors (4156705).

18011903 is a wasteful number, since it uses less digits than its factorization.

18011903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197953.

The product of its (nonzero) digits is 216, while the sum is 23.

The square root of 18011903 is about 4244.0432372915. The cubic root of 18011903 is about 262.1318946269.

Adding to 18011903 its reverse (30911081), we get a palindrome (48922984).

The spelling of 18011903 in words is "eighteen million, eleven thousand, nine hundred three".