163663665138 has 12 divisors (see below), whose sum is σ = 354604607838. Its totient is φ = 54554555040.

The previous prime is 163663665131. The next prime is 163663665161. The reversal of 163663665138 is 831566366361.

163663665138 is a `hidden beast` number, since 1 + 6 + 3 + 6 + 63 + 66 + 513 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 144884525769 + 18779139369 = 380637^2 + 137037^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (163663665131) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4546212903 + ... + 4546212938.

Almost surely, 2^163663665138 is an apocalyptic number.

163663665138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

163663665138 is an abundant number, since it is smaller than the sum of its proper divisors (190940942700).

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

163663665138 is a wasteful number, since it uses less digits than its factorization.

163663665138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9092425849 (or 9092425846 counting only the distinct ones).

The product of its digits is 8398080, while the sum is 54.

The spelling of 163663665138 in words is "one hundred sixty-three billion, six hundred sixty-three million, six hundred sixty-five thousand, one hundred thirty-eight".