18943111 has 8 divisors (see below), whose sum is σ = 20974464. Its totient is φ = 16963320.

The previous prime is 18943103. The next prime is 18943121. The reversal of 18943111 is 11134981.

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

It is not a de Polignac number, because 18943111 - 2³ = 18943103 is a prime.

It is a super-3 number, since 3×18943111³ (a number of 23 digits) contains 333 as substring.

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 18943111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18943121) 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, 12115 + ... + 13588.

It is an arithmetic number, because the mean of its divisors is an integer number (2621808).

Almost surely, 2^18943111 is an apocalyptic number.

18943111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18943111 is a deficient number, since it is larger than the sum of its proper divisors (2031353).

18943111 is a wasteful number, since it uses less digits than its factorization.

18943111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25781.

The product of its digits is 864, while the sum is 28.

The square root of 18943111 is about 4352.3684356911. The cubic root of 18943111 is about 266.5735780985.

It can be divided in two parts, 1894 and 3111, that added together give a palindrome (5005).

The spelling of 18943111 in words is "eighteen million, nine hundred forty-three thousand, one hundred eleven".