18903818 has 8 divisors (see below), whose sum is σ = 29122212. Its totient is φ = 9196416.

The previous prime is 18903817. The next prime is 18903869. The reversal of 18903818 is 81830981.

It can be written as a sum of positive squares in 2 ways, for example, as 18809569 + 94249 = 4337^2 + 307^2 .

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

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18903811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127655 + ... + 127802.

Almost surely, 2^18903818 is an apocalyptic number.

18903818 is a deficient number, since it is larger than the sum of its proper divisors (10218394).

18903818 is a wasteful number, since it uses less digits than its factorization.

18903818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255496.

The product of its (nonzero) digits is 13824, while the sum is 38.

The square root of 18903818 is about 4347.8521134004. The cubic root of 18903818 is about 266.3891359155.

The spelling of 18903818 in words is "eighteen million, nine hundred three thousand, eight hundred eighteen".