18918159 has 8 divisors (see below), whose sum is σ = 27164592. Its totient is φ = 11641920.

The previous prime is 18918157. The next prime is 18918181. The reversal of 18918159 is 95181981.

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

It is not a de Polignac number, because 18918159 - 2¹ = 18918157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18918159.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18918157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 242502 + ... + 242579.

It is an arithmetic number, because the mean of its divisors is an integer number (3395574).

Almost surely, 2^18918159 is an apocalyptic number.

18918159 is a deficient number, since it is larger than the sum of its proper divisors (8246433).

18918159 is a wasteful number, since it uses less digits than its factorization.

18918159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485097.

The product of its digits is 25920, while the sum is 42.

The square root of 18918159 is about 4349.5010058626. The cubic root of 18918159 is about 266.4564824686.

The spelling of 18918159 in words is "eighteen million, nine hundred eighteen thousand, one hundred fifty-nine".