18108493 has 8 divisors (see below), whose sum is σ = 19552568. Its totient is φ = 16671744.

The previous prime is 18108487. The next prime is 18108509. The reversal of 18108493 is 39480181.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 777924 + 17330569 = 882^2 + 4163^2 .

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

It is a 5-Lehmer number, since φ(18108493) divides (18108493-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 18108493 - 2⁹ = 18107981 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 (18108413) 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, 4021 + ... + 7237.

It is an arithmetic number, because the mean of its divisors is an integer number (2444071).

Almost surely, 2^18108493 is an apocalyptic number.

18108493 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18108493 is a deficient number, since it is larger than the sum of its proper divisors (1444075).

18108493 is a wasteful number, since it uses less digits than its factorization.

18108493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3663.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 18108493 is about 4255.4075010509. The cubic root of 18108493 is about 262.5996259788.

The spelling of 18108493 in words is "eighteen million, one hundred eight thousand, four hundred ninety-three".