18538361378 has 8 divisors (see below), whose sum is σ = 28559097372. Its totient is φ = 9018662256.

The previous prime is 18538361377. The next prime is 18538361381. The reversal of 18538361378 is 87316383581.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14052442849 + 4485918529 = 118543^2 + 66977^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18538361371) 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, 125259125 + ... + 125259272.

Almost surely, 2^18538361378 is an apocalyptic number.

18538361378 is a deficient number, since it is larger than the sum of its proper divisors (10020735994).

18538361378 is a wasteful number, since it uses less digits than its factorization.

18538361378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250518436.

The product of its digits is 2903040, while the sum is 53.

The spelling of 18538361378 in words is "eighteen billion, five hundred thirty-eight million, three hundred sixty-one thousand, three hundred seventy-eight".