18135855 has 48 divisors (see below), whose sum is σ = 33718464. Its totient is φ = 8985600.

The previous prime is 18135853. The next prime is 18135881. The reversal of 18135855 is 55853181.

It is not a de Polignac number, because 18135855 - 2¹ = 18135853 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18135851) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 115437 + ... + 115593.

It is an arithmetic number, because the mean of its divisors is an integer number (702468).

Almost surely, 2^18135855 is an apocalyptic number.

18135855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18135855 is a deficient number, since it is larger than the sum of its proper divisors (15582609).

18135855 is a wasteful number, since it uses less digits than its factorization.

18135855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336 (or 333 counting only the distinct ones).

The product of its digits is 24000, while the sum is 36.

The square root of 18135855 is about 4258.6212557587. The cubic root of 18135855 is about 262.7318224206.

The spelling of 18135855 in words is "eighteen million, one hundred thirty-five thousand, eight hundred fifty-five".