18113549 has 4 divisors (see below), whose sum is σ = 18128220. Its totient is φ = 18098880.

The previous prime is 18113521. The next prime is 18113569. The reversal of 18113549 is 94531181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1155625 + 16957924 = 1075^2 + 4118^2 .

It is a cyclic number.

It is not a de Polignac number, because 18113549 - 2¹⁶ = 18048013 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 (18113509) 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, 5294 + ... + 8015.

It is an arithmetic number, because the mean of its divisors is an integer number (4532055).

Almost surely, 2^18113549 is an apocalyptic number.

It is an amenable number.

18113549 is a deficient number, since it is larger than the sum of its proper divisors (14671).

18113549 is a wasteful number, since it uses less digits than its factorization.

18113549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14670.

The product of its digits is 4320, while the sum is 32.

The square root of 18113549 is about 4256.0015272554. The cubic root of 18113549 is about 262.6240635022.

The spelling of 18113549 in words is "eighteen million, one hundred thirteen thousand, five hundred forty-nine".