18519138 has 32 divisors (see below), whose sum is σ = 44896320. Its totient is φ = 5611680.

The previous prime is 18519133. The next prime is 18519157. The reversal of 18519138 is 83191581.

18519138 is a `hidden beast` number, since 1 + 8 + 519 + 138 = 666.

It is not an unprimeable number, because it can be changed into a prime (18519133) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14995 + ... + 16182.

It is an arithmetic number, because the mean of its divisors is an integer number (1403010).

Almost surely, 2^18519138 is an apocalyptic number.

18519138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18519138 is an abundant number, since it is smaller than the sum of its proper divisors (26377182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18519138 is a wasteful number, since it uses less digits than its factorization.

18519138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31199 (or 31193 counting only the distinct ones).

The product of its digits is 8640, while the sum is 36.

The square root of 18519138 is about 4303.3868057612. The cubic root of 18519138 is about 264.5697920585.

The spelling of 18519138 in words is "eighteen million, five hundred nineteen thousand, one hundred thirty-eight".